Tuesday, Symposium: Cortical sources . . . 37

MET,BOLICPVMP~NG IN INSECT LKSCIE ,WD RESTING MEMBRXW ELECTROGENESIS Comparison of electrical activity and ionic currents in an isolated M.J. KATKOWSKA & B. GRAPEL. N. Copernicus Univ., Inst. of Biology and axon and in an isolated neuron. Environmental Protection. Dept. of Animal Physiology, To&. Poland Stankiewicz M.', Grolleau F.~,Lapied B.~,Kadziela w.', Pelhate M.~ A studj of the literature concerning the resting potential (RP) of insect muscle Inst, of Biology and Environment Protection. N.Copernicus Univ , Torun. Poland reveals a number of apparent departures from the situation found in other (I),Lab.of Neurophysiology. EREA CNRS 120. Angers, France (2). excitable cells. The Insects. adult Colorado beetle and mealworm, and mealworm The comparative approach to investigation of the axonal and larva. chosen to this study differ much in their haemolymph ionic content (e.g neuronal mechanisms underlying rythmogenesis in invertebrates has lead Colorado beetle's haemolymph contains only 2 mmol.l-' of NaC) and so they have to an important conclusion that rythm generation is the result of complex ditferent ion~c requirements for the resting membrane potential (RMP) interactions between cellular, synaptic and network properties. The aim of maintenance and the contnbution of pumps to it. The present study examines the this study is to compare the membrane properties of insect giant axon, tlme dependence of the RP In muscles of studied insects and tries to determine the which propagates action potentials and insect neurosecretory cells called role of metabolic pumping in the genesis of tlus potentla1 using of sodium pump dorsal unpaired median (DUM) neurons involved in the modulation of idubitor - ouabain and in the case of Colorado beetle, K-H pump inhibitor - SCH skeletal and/or visceral muscles via the release of octopamine. Giant axon 28080. Eqxriments were performed in situ on Indirect flight muscles of adult and DUM neuron are endowed with a specific set of ion currents that shape Colorado beetle and mealworm, and on ventral longitudinal muscles of mealworm and define their integrative properties. For a detailed study of the larva by "soaking" the muscles in standard (respective for each of Insects studied) biophysical and pharmacological properties of these currents, application or modified salines for 2h. and impaling several cells in each preparation. The of double oil-gap method and patch-clamp technique to giant axon and conventional microelectrode technique was used. The control mean values of DUM neuron respectively, has proven a useful strategy. The axonal muscle RP in adult Colorado beetle and mealworm and mealworm larva, membrane properties can be described by a capacitance in parallel with measured just after the equil~brationtime, were, respectively. 75.0, 50.6 and 38.3 three types of currents: a fast transient sodium current sensitive to mV. and only slightly decreased with time. In Colorado beetle's muscles. tetrodotoxin, a delayed rectifier (DR) potassium current blocked by 4- application of I mmol.1-' ouabain caused a membrane hyperpolarizationof around aminopyridine and a leak current. They allow to generate only short 6 mV after 90 and 120 min. Application of 1 mmol.l-' SCH 28080 resulted in a evoked action potentials (0.5 ms in duration) however at high frequency slight decrease of the RPvalue. In the muscles of adult mealworm. ouabain caused (up to 300Hz). By contrast DUM neurons spontaneously generate electrical a slight. gradual hyperpolarizatlon of the RP (by 2.8 and 4.5 mV after 1 and 2h, activity in the abscence of synaptic input or other external stimuli. DUM respectively). Essentially identical results have been obta~nedon ventral muscles neurons can fire repetitive impulses with remarkably regular intewals. The of mealworm larva. Thus. it seems that the skeletal muscles of studied insects do study of ionic mechanisms underlying this spontaneous electrical activity not contaln an ouabain-sensmve metabol~cmechanism, the functioning of which reveals that DUM neuron soma possess voltage-dependent Na channels is necessary for long-term maintenance of the RMP. In insects, like Colorado responsible for the depolarizing phase and background Na channels beetle, with unconventional ion levels in their haemolymphs, at least the NaC playing a role in driving the membrane potential to threshold of action gradient may be in the reverse direction, and the outward K- gradient much potential. In addition DUM neurons also display multiple K+ currents such reduced. The operation of the classical NaA-K+pump would not be suitable for as IKN,, IKca, IKDR and IKA like, involved in the repolarization, these conditions, and, therefore, such pumping mechanism may not be present in afterhyperpolarization and regulation of the firing frequency. Moreover two these msects. If an electrogenic pump is present in muscle fibers of studled distinct types of low voltage activated ca2+ currents: a transient and a insects, lts properties dlffer appreciably from those described for the electrogenic maintained current have been described. The first one is involved in the sodium pump which appears in many nerves and muscle cells. initial part of the predepolarization and the second one participates in the last two-third of this predepolarization.

Symposium 4 - Cortical sources of oscillation

DOES IN VITRO THETA-LIKE ACTIVITY REFLECT Oscillatory brain dynamics in auditory and visual PHYSIOLOGICAL AND PHARMACOLOGICAL PROPERTIES system OF EPILEPTIFORM DISCHARGES ? Jan Konopacki C. Pantev, Muenster Department of Neurobiology, University of lodz, Rewolucji 1905 No 66,90-222 Lbdz, Poland.

The generation of EEG theta rhythm in the mammalian limbic cortex is a prime example of rhythmic activity that involves central mechanisms of oscillations and synchrony. In 1986 we demonstrated for the first time that bath perfusion of hippocampal slices with the cholinergic agonists resulted in theta-like oscillations. The coincidence in properties of the on vivo and in vitro recorded Not received rhythmic slow activity leads to a general conclusion that the generation of theta in both these preparations share common mechanisms. However, one more issue should be addressed. The known ability of CCH induced epileptiform activity (when administered in an appropriate concentration) would suggest that theta-like activity also has an epileptiform component. The theoretical implication of this suggestion would be that theta-like activity reflects the physilogical and pharmacological properties of epileptiform discharges. The experiments we have been conducting for the last 10 years on slice preparations suggest that the in vitro induced theta-like activity does not reflect the physiological and pharmacological properties of epileptiform activity. Since it was much more in common with the naturally occuring theta then with epilepsy, we have adapted the term "theta-like" activity. 38 Tuesday, Symposium: Cortical sources .

Transient and Steady State Responses of Somatosensory and Neuromagnetic Sensorimotor Rhythms L4uditoryCortex in Humans Alfons Schnitzler L.E Roberts" D. Bosnyak", W. Gaetz" D. cheyneh, C. Pantev'. Department of Neurology, Heinrich-Heine University, Dusseldorf, C ahm mi as^, and H weinbergh Departments of Tsychology Germany and dNuclear Medicine, hlcMaster University, Hamilton, Canada, rain Behaviour Laboratory, Simon Fraser University, The human cerebral cortex generates a variety of rhythmic Vancouver, Canada; 'Institute of Experimental Audiology, oscillations detectable directly from the cortex or the scalp. The University of Muenster, Germany. recent development of whole scalp neuromagnetometers has made non-invasive studies of oscillatory brain activity feasible in awake "Transient responses" are responses evoked by stimuli human subjects In this presentation, results of studies will be presented at long interstimulus intervals such that the brain surveyed which investigated the human magnetic mu rhythm returns to its initial state before the next stimulus occurs. If the originating close to the primary somatosensory hand area and stimulus is presented at shorter intervals so that responses to consisting of dominant frequency components near I0 Hz and 20 successive stimuli overlap in time, the procedure is referred to Hz. Sources of tlie 20 Hz component cluster anterior to those of the as a "steady state procedure" and the response as a "steady state 10 Hz component suggesting a dominant contribution of the response" (Regan, 1989). We have adopted steady state precentral motor cortex 10 Hz and 20 Hz rhythms exhibit a procedures for imaging sensory representations in experiments characteristic modulation after electric median nerve stimulation, on cortical plasticity in humans, because these procedures afford with a suppression immediately after the stimuli and a strong rapid acquisition of data and concentrate signal energy at known rebound above the prestimulus level within 500 Ins aftenvards This repetition rates. Present findings suggest that sensory rebound is left-hemisphere dominant and differentially affected by representations or "maps" derived from steady state procedures various motor tasks and passwe tactile stimulation of the hands Interestingly, the 20 Hz component is also modified when the differ from maps based on transient methods. The relation of subject imagines the performance of a motor task, such as steady state and transient responses is discussed. exploratory finger movements, indicating that the primary motor cortex is active in motor imagery In contrast, simultaneously Supported by NSERC and MRC (Canada), DFG (Germany), and recorded evoked responses in the somatosensory cortex are not NATO affected by motor imagery Obviously, rhythmic sensorimotor activity and stimulus-locked evoked responses retlect different aspects of signal processing in tlie sensorimotor coltex

ATTENTION RELATED OSCILLATORY ACTIVITY WITHIN Nonlinear Oscillations in Cortical Structures SENSORY SYSTEMS Ilonal~kZJ. \\ itte 011 A. Wrobel Nencki Institute of Experimental Biology, 3 Pasteur St., 02- 093 Warsaw, Poland Depurtnicnt of \curoloyy. I nlierszfy of Duswldorf IRG Oscillatory signals of three frequencies (alpha, beta, gamma) are Neural mass activity produces irregular time series such as those exceptional in the sense that they are the least damped when transmitted measured in EEG and MEG (magnetoencephalography). If we do through the sensory channels. The hnctional significance of alpha band not view EEG and MEG as a stochastic signal, e.g., as the noise is usually discussed in relatlon to ~tsrole in gating the sensory of the brain's engine (or an autoregressive process), but, at least information during sleepiarousal transition mechanisms; whereas the partially, as a measure of lawful and deterministic regulatory pro- gamma band might provide coactivation frequencies between cells from cesses of neuronal assemblies, we can apply the measures from the different brain areas during feature integration processes. The third band theory of nonlinear dynamical systems (chaos theory) to characterize at the beta frequencies (15-30 Hz), has been commonly neglected with and quantify the brain mechanisms at work. Even if the theoretical respect to its possible physiological functions. premises cannot be fulfilled, we may use the theory of chaos to define We have adopted two different experimental paradigms to study and quantify complexity as it appears in a given time series. Here, we the activity of the sensory systems during active behavior. During the show some examples of pure "chaotic" behaviors extracted in the classical conditioning paradigm we have found that the ERPs evoked by MEG and EEG experiments on epilepsy and normal spontaneous vibrissae stimulation in the barrel cortex of the rat increased in activity by apply~nglocal Lyapunov exponent in the running window amphtude with first reinforcement. This change was due to increased technique. This method allows also to detect sudden changes of the power of alpha, beta and gamma components of Fourier-transformed dynamics in the measured time series. Those changes are biological ERPs, possibly indicating ihat the novel situation activated the vibrissa- analogs to critical transitions in a course of physics. They confirm barrel sensory channel. We also observed that local field activity the nonstationary character of EEG/MEG and, in addition, hold recorded from many sites in lateral geniculate nucleus and primary promise to be used as the predictors of epileptic seizures. Using visual cortex of cats attending to visual stimuli during differentiation the multichannel techniques of EEG and MEG increases also spatial task contamed an enhanced amount of power within the beta band as information about the localization of oscillatory centers. The loss of compared to activity observed during audltory or erroneously ended the signal stability is also observed in the interictal states. Supposing visual trials. This activity comprised of short bursts of oscillations. They that the interictal oscillators are localized in the same way as the were found to correlate in time with gamma-frequency bursting. ictal ones leave us to expect, in case of focal epilepsy, that positions We propose that attention preactlvates the specific functional of oscillatory centers correspond to the position of epileptic foci For connections within sensory systems with the use of the beta frequency cases of epilepsy in which the focus is difficult to localize there IS a camer. In consequence it would provide a necessary background chance to indicate the side of the functional distortion, what may actlvatlon to allow binding of the requlred cell assemblies with gamma be of diagnostic value. synchronized oscillations. Tuesday, Symposium: Molecular and morphological .

Symposium 5 - Molecular and morphological aspects of neural apoptosis nunervous system (PNS). These deficits are mainly of CsA-sensitive component, NFATp, and the AP-1 transcription due to an increase in the rate of cell death during embryonic factor composed of Fos and Jun family proteins. Some neurologcal development. However, no apparent deficits were dectected in the complicat~onsand cytotoxic effects of CsA therapy have been central nervous system (CNS) of these animals. In contrast to reported but precise mechanism of CsA action is unknown. To get sensory neurons, the development of the CNS neurons continues Insight into possible mechanism of CsA cytotox~ceffect, we during the first two weeks of life. trkB (-/-) mutant mice with a invest~gatedthe effects of CsA (Sandimun, Sandoz) on rat C6 predominant C57BV6 genetic background have an increase in their glioma cells. Wehave found that CsA exerts antiproliferat~veeffect life span compared to the early generations of animals. In this 011 glioma cells and induces cell death which showed all features study, we show that trkB (-I-) mice have a significant increase in cell tvpical of apoptosis. Cells treated w~th75 nig/n~lCsA exh~b~ted death in different regions of the brain after the first posmatal week. cell body shrinkage and chromatin condensat~onfollowed by This cell death, that is more severe in the oldest surviving rrkB (-/-) fragmentahon; death was accon~paniedby the appearance of DNA mutant mice, is apoptotic in nature. The most affected region in the "ladder" upon gel electrophoresis; apoptotic changes were brain is the dentate gyms of the hippocampus, although, significant abrogated bv the cycloheximide, a inhibitor of proteln synthesis. increase in pyknotic cells was also detected in cortical layers (11-111 Us~ngElectrophoretic Mobll~tyShift Assay we studled DNA and V-VI). In these regions, some of the pyknotic cells are labeled binding act~vitiesof AP-1 and KFAT transcription factors during with different calcium-binding proteins. Furthennore, the survival CsA-induced apoptosls. Besides the elevation of the AP-1 DNA of hippocampal neurons and motor neurons after axotomy lesions binding act~vitybeginning at 6 hr after CsA addition, we observed were decreased in mice lacking TrkB tyrosine kinase receptors. remarkable changes in the composition of AP-1 complex in dylng These results suggest that neurotrophin signaling through TrkB cells (24 hr after CsA treatment). These changes were man~festedby receptors is essential for late posmatal survival of CNS neurons. the appearance ofJunB and JunD protelns In the complex as well as Moreover, TrkB signaling appears to protect CNS neurons from the increase of c-Junprotein. Our findings suggest that both Increase axotomy-induced cell death. and differences In AP-1 compos~tionmay be responsible for speclhc role of this factor In the regulat~onof apoptosis. The NFAT DNA binding act~vitywhich was present in proliferating C6 glioma cells, decreased to undetectable level as early as 6 hr after CsA- treatment. It rases a possibility that KFAT is the prlmary target for Csa in glioma cells and the mechanism ofCsA action in glial cells can be slnlllar to that operating in lvmphold cells.

EXCITOTOXICITY OF KAIh'IC ACID AND QUINOLINIC Tissue Inhibitor of Metalloproteases-1 (TIMP-I) is Differentially ACID: ANIMAL AND TISSUE CULTURE STUDIES. Induced in Neurons and Astrocytes Following Seizures and Cerebral Ewa Matyja Ischemia: Evidence for Developmental-, Immediate Early Gene- and Lesion-Response Department of Neuropathology, Med~cal Research Centre, Pol~sh S. R~vera, E. Tremblaq, S. Tlmilt, 0. Canals, Y. Ben-An, and M. Academy of Sc~ences,Paw~nslaego 5 St., 01-106 Warsaw, Poland Khrestchatisky Kanic ac~d(KA) and quinol~nicac~d (QUIN), exo- and endogenous Unl\erslte Rene Dcscartcs, Pans V. INSERhl Un~te-29 123 Bld. de Port Ro~al, excitatory ammo ac~ds of both neuroexcltatory and neurotoxic 75014, Pans, France propertles, have been widely appl~edIn experimental neuropathology. The Tlssue Inh~b~torof Metalloproteixes-1 (TlhlP- 1) 1s a 28.5 kDa secreted The alm of the present stud~eswas to evaluate the dynam~csand gl~coproteln.Although consldereda multlfunct~onalmolecule that possesses gro\\ th promoting propertles and mltogenlc actlvlty, TIMP-I 1s mostly recogn17ed as an pattern of ultrastructural changes Induced by these neurotoxic lnhlb~torof matn.; metalloproteases (LIMP\). MMPs constitute a famll! of me- compounds In an~malmodels of Huntington's d~seaseor ep~lepsyand blndlng and Ca++-dependent endopeptldases. The elcessne clealage of the In organotyplc or d~ssoc~atedcell cultures derived from selected extracellular matn'. (ECM) asscclated 611th an lmbalance of the MMPs,'TlhlPs ratlo reglo& of rodent bra~nsBoth m vivo and rn vitro, typical excitotoxic has been correlated a~ththe ln\asl\e p~tentlalof bran tumor cells, and \r~ththe changes consisted of progressive degeneration of large striatal h~stopathogcncs~sof ~nflammatory-relatedd~seases. Nedn~ct dl. (1993) lsolatcd neurons and pyram~dal h~ppocampal cells and axon-sparing, TlhlP-1 In the CNS as a candldakplastlc~tq gene In hamate (KA)-treatedrats. We postulate that controlled protcolqs~s1s cmclal In the dexelopment and plastlat) of postsynaptic les~onsaccompanied by extensive fibnllar gliosis Data the CNS, whereas excessl\c proteol)s~s contnbutcs to \anous neuropathologles. from in vitro expenments indicated that gl~alfibnllary changes should We ln\est~gatcdin vivo the expresslon of the tlssue lnh~b~torof metalloproteascs-1 be cons~deredas a primary response of astroglia to excitotoxins, (TIUP-I) In the rat CNS follo\rlng KA-~nducedc\c~loto\lc selzurcs and cerebral independent of neuronal damage Delayed QUIN-induced neuronal lschemla. 1r1 sirlr hqbndlratlon re\ealed that TIMP-l mRNA 1s rapidl) Induced In and gl~alpathology has been evaluated In long-lasting experiments in most reglons of the adult forebran, follo\r~ngpatterns of ncuronal h)peract~\~t). vivo. A tlssue culture model allowed to study the direct effect of Neuronal actlllt) appems to be necessac but not sufflc~entto tnggcr TlhlP-1 ~nduct~on,slnce 11 1s not obsencdln selnng 10-day old pups. Follo\rlng selLures, various concentration of KA or QUIN appl~edat d~fferentstages of the rap~dlnductlon of TIMP-I 1s not pre,ented b) lnh~b~tlonof proteln s)nthes~s. tissue maturation and cell d~fferent~ation.An appropr~atelymod~fied suggestlng that TIMP-1 1s Induced In neurons as an lmrnedlate earl) gene. The culture environment was used to demonstrate the neuroprotective liltla1 neuronal upregulat~on1s follo\red by enhanced expression In astrocytes, a\ effect of calcium channel blockers: n~mod~p~ne,verapamil and assessed by double label~ngexpenmcnts In the h~ppocampus,rapld Increixes In divalent cations. zinc, magnesium against QUIN neurotoxic~ty. mRXA are follorved bq dela)ed Increases In TlhlP-1 lmmunoreactl\lt) In the QUIN-induced m~tochondnalcalcium overload and its prevention by pensomatlc and dendr+a\-on~careas.suggestlng secretion of the proteln. Three day after KA treatment, strong lmmunoreactlvlt) 1s found In astrixqtes and In the cell nimodipine, was visualized by oxalate-pyroant~monatecytochemical bodies and dendroa~on~cprojcctlonsof reslsrant neurons such as the dentate granule technique for electron microscopy. The results support the important cells. Taken together, the results suggest that TIMP-I may be instrumental for role of calc~um entry In the development of delayed exc~totoxic neurons and astrocytes In coupllng earl) cellular elents triggered b) se~~uresa~th neuronal damages the regulat~onof long-last~ngchanges in\ol\ed In tlssue reorganl/atlon and,'or neuroprotectlon. 40 Tuesday, Symposium: Neurobiology of addiction

Neurodegeneration-associated expression of cathepsin D. M. Hetman. R.K. Filiokowski. W. Danvszx. L. Kaczmarek. Nencki 1nsthe, ~ariaw; 'M&Z&CO, erankfurtl~ain, Cathepsin D (CatD) is major lysosomal aspartic protease. a protease, CatD can be involved in cell destruction mechani including those activated in neurotoxic insults. In this study expression of CatD was determined in two neurotoxic condi in rat brain. Kainic acid (KA), agonist of glutamate receptor evokes in rats seizures followed by massive neurodegenerati mainly in the structures associated with limbic system. MK- is an antagonist of NMDA receptor. Administration of MK- to rats in doses exceeding 1 mglkg causes degeneration of fc percent of neurons in retrosplenial cortex. Increased CatD expression was observed in both KA- and MK-801- evoked neurodegeneration. This increase was evident at both mRNP protein levels as determined by northern blotting and immunohistochemistry. In both conditions the increase of mRNA level was well established 24 hours after the treatmer and reached maximal values 72 hours after the treatment. Immunohistochemistry for CatD revealed intense staining observed mainly in cells presenting features of degenerating neurons. This localization was further confirmed by compal the patterns of CatD and GFAP immunoreactivities. In ordel study the mechanisms of neuronal death activated by KA ar MK-801, DNA fragmentation was studied using agarose gel electrophoresis and in situ detection techniques. KA was fol to evoke apoptotic, ladder-like fragmentation of DNA in thc structures affected by the toxin. Degenerating cells appearir retrosplenial cortex in response to MK-801 were shown to contain no DNA, as revealed by DNaseI pretreatment of bra sections and subsequent TUNEL staining for fragmented Dl This result suggests rapid degradation of cellular DNA in th course of MK-80 1-evoked neurodegeneration. Thus, increa expression of CatD seems to be a common element of degenerative cascades triggered by different compounds an differentially engaging DNA fragmentation.

Symposium 6 - Neurobiology of addiction

IS THERE A COMMON MECHANISM OF Opioids and Addictive Processes DRUGS OF ABUSE? B Przewlocka Albert Herz, Max-Planck-Institute for Psychiatry, Department of Molecular Neuropharmacology, Institute of D-82152 Martinsried, Germany Pharmacology, Polish Academy of Sciences, Krakow. Poland The great progress made in opioid research during the last two decades offers new perspectives for the understanding (and possible treatment) not only for opioid addiction but also of Desp~tee\tensl\e studlcs the neurochenucal bas~sof drug addct~on addictive processes in general. IS onl~pan11 understood A number of data suggest that the InteractLon of The study of motivational effects of opioids revealed p- and endogenous op~oldsand the dopanunerg~cmesollnib~c nstenl IS cnt~calh 6-agonists as positive reinforcers in animal models (e.g. place- ~mohedIn the neurochenucal mechamsm of tolerance and dependence on conditioning), whereas r-agonists were found to be aversive. drugs of abuse belonging to Merent groups of phannaceutlcs Recent11 There is much evidence that the dopaminergic mesolimbic reward a~dencehas been accu~llulatedthat NMDA receptors and mtnc oude dre also ~nlpllcatedIn the effmts of drugs of abuse slnce the Increased le~elof system mediates these effects: p- and 6-agonists increase, lutnc oude IS a consequence of the NMDA receptor actnatlon In fact r-agonists decrease dopamine release in the Nucleus blockade of the NMDA receptor and ~dub~t~onof mtnc oude nnthase lead accumbens. Obviously,'the same mesolimbic pathway is to a dela\ In daelop~ngtolerance and counteracting some beha\loural modulated by two opposing tonically active endogenous opioid nmptoms of mthdranal systems. We found that chron~cadnutustrat~on of different drugs of abuse (morphne The mesolimbic reward pathway mediates also motivational pnchost~~llulants ethanol) Increased the nnthet~c actl\~& of effects of other drugs of abuse. There is increasing evidence that prochnorphnerg~cneurons es~clall~dunng the~rlate mthdraual That opioid mechanisms are involved in such effects of psycho- effect nas antagomzed h pretreatment alth L-NAME a mtnc oude stimulants, e.g. in the sensitization for the rewarding effects of snthase lnhbltor On the other hand kappa op~o~dreceptors nere donn- cocaine. The addictive properties of alcohol seem to involve regulated as a result of the Increased release of prhnorplun-demed endogenous opioids too, explaining the promising effects of peptldes We also obsencd doan-regulat~on of NMDA receptors and opioid antagonists to prevent relapse in alcoholics. upregulatlon of mu op~o~dreceptors In certaln bran structures The obtalned data ~n&catethat a prolonged exposure to drugs of abuse results In an enhanced actl\lt\ of the prochnorphln nstem and that the WAN0 pathma\ ma) modulate ths adaptne neuronal response Thf~~ork HUT ru[)j~orre~ih\ grmzty fro~r~FC' CIP I('[ 94-0226 ar7d rtatuloq actnit) h\ hR\ llar~uu Tuesday, Symposium: Neurobiology of addiction 41

DISTRIBUTION AND REGULATION OF p-OPIOID RECEPTORS. The effects of acamprosate on opiate dependenceladdiction V Hollt. A Becker. T Koch S Schulz and A Z~mpr~chDepartment of R. Spanagel', I. Sillaber', C. Kirschke', W. Zieglggnsberger', J. Stewart' and Y. Pharmacolog!, Otto \on Guer~cke Un~vers~t!, D-39120 Magdeburg. Sbaham3 German! 'Max-Planck-Institute of Psychiatry, Clinical Institute, Munich, Germany 'Concordia University, Montreal, Canada The rat p op~o~dreceptor exlsts In tao sof forms termed rMORl and 'Addiction Research Foundation, Toronto, Canada rMORlB \\h~chare generated b~ an alternate spl~c~ngevent at the C- Acamprosate prevents relapse in weaned alcoholics, however, its efficacy in p termmus When stabl~transfected Into CHO-K1 cells both op~o~d relapse prevention in other drug abusers has not been examined so far. It is receptor sof forms sho~similar afin~tlesto op~o~dcompounds and nere suggested that there exist similarities in the neurobiological mechanisms equall~ effectne In medlat~ng ~nh~b~t~onof forskohn-induced CAMP underlying alcohol and opiate addiction. Therefore, we were interested in the format~on b\ agonlsts In add~t~on,both p receptor varlants med~ate question whether acamprosate also interferes with opiate dependence processes. Increases In mtracellular calc~umconcentratlons and lnos~toltr~phosphate The action of acamprosate was studied on morphine-induced behavioural formation m response to slm~larconcentrations of op~o~dagonlsts In sensitization procedures (locomotor activity and conditioned place preference). constrast, transfected cells evpressmg rMORlB \\ere much more resistant Acamprosate (200 mgkg) completely abolished the expression of morphine- to desens~trzat~onafter prolonged exposure to agonlsts than cells expressmg induced behavioural sensitization, however, it did not influence the locomotor rMORl The reglon of the C-tennus In ~ihlchrMORl d~ffersfrom effects of an acute morphine injection in drug-naive animals. In addition rMORlB contalns one potentla1 phosphonlat~on s~te(thr 394) Polnt microdialysis data revealed that augmented dopamine release in the nucleus accumbens following intermittent context-dependent injections of morphine is mutatlon of thr 394 to an alanme or truncation of the C-temnus of rMORl also abolished by acamprosate pretreatment. In contrast, preliminary data indicate resulted In a slower desens~t~zat~onklnet~c of rMORl s~mllarto that of that acamprosate neither affected intravenous heroin self-administration during rMOR1B Th~s~nd~cates that phosphonlat~onof the C-temnus of rMORl the maintenance phase nor influenced reinstatement of drug-seeking induced by a pla!s an important role m receptor desens~t~zat~on heroin priming injection or footshock during the relapse phase. Furthennore Us~ng specific antlsera MORIB-l~ke Immunoreactlvlt) could on]\ be acamprosate was tested in a model of conditioned opiate withdrawal: rats were locallzed In the plexifonn la\er of the olfacton bulb \\hereas MOR1-l~ke trained to lever-press for food reinforcement on a FR10. The animals were then mununoreactlvlt! sho\+ed the known d~str~but~on~n man! reglons of the implanted with morphine pellets and naloxone was given in the operant chambers braln and spmal cord of rats and mlce Interestlngl!, m Dl dopamine paired with a smell stimulus. On the test day rats were exposed only to the receptor defic~entmlce the patch\ d~stributlonof MORl m the striatum and conditioned stimulus associated with the state of withdrawal. The conditioned nucleus accumbens could not be obsened In contrast to the n~ldt~pe stimulus acquired significant behaviour-disruptive properties (e.g. a strong decrease in lever-presses), however, acamprosate did not prevent this conditioned animals In add~t~on,repetitive appllcat~onof mo~ph~neresulted m a gradual response. In conclusion, although acamprosate prevents the expression of Increase In the locomotor actl\lt! In the u~ldt\pe mlce but d~dnot affect morphine-induced sensitization it does not interfere with reinforcing effects of the locomot~on of the a~ld-t!pe an~mals These results prov~de futher intravenous heroin, relapse to heroin-seeking and conditioned opiate withdrawal. ebldence for the ~mportantrole of strratal Dl receptors In the actlon of p- op~o~dagonlsts

REDUCTION OF ALCOHOL INTAKE IN ALCOHOL- REDCCTIOS OF ALCOHOL ISTAKE BY TACHYKIKIK NK-3 PREFERRING RATS BY TACHYKININ NK-3 RECEPTOR RECEPTOR .\COlrllSTS IS ALCOHO1.-PREFERRING RATS: AGONISTS: A SEARCH FOR THE SITE OF ACTION. A SEARCH FOR THE MECHANISM OF ACTION. Massi M. C~ccocioppoR, *Panocka I, Polidori C, De Caro G. *Panocka I, C~ccocioppoR, Polidori C, De Caro G, +Froldi R, Massi M. Department of Pharmacol. S~I.Exp. Med., University of Camerino, Italy; Department of Pharmacol. Sci. Exp. Med., University of Camerino. Italy; *institute of Genetics and Animal Breeding. Jastrzebiec, Poland. *Institute of Genetics and Animal Breeding, Jastrzebiec, Poland; +Institute of Intracerebroventr~cular(ICV) ~njectionsof tachyklnin (TK) NK-3 receptor Legal Medicme, University of Macerata, Italy. agonlsts reduce alcohol intake m alcohol-preferring rats. The NK-3 receptor Injections of tachykinin (TK) NK-3 receptor agonists in the nucleus basalis agonist senkt~dereduces ethanol intake also by subcutaneous injection, but doses magnocellularis (NBM) reduce alcohol intake in rats. The present study was about 1000 times higher than those effective by ICV inject~onare required, aimed at investigating the mechanism of the action on alcohol intake of the suggesting a central site of action. The present study evaluated the sens~tivityof NK-3 receptor agonlst NH2-SENK, in rats selectively bred for high ethanol several brain sltes to the effect of the NK-3 receptor agonist preference. 1) Taste reactivity. Since NK-3 receptor agonists influence taste [~s~~~~,~e~he~]substanceP(5-ll), also referred to as NH2-senktide (NH2- reactivity to NaCl solutions, the present study evaluated whether they may SENK) on alcohol intake in genetically selected alcohol-preferring rats, which modify also taste reactiv~tyto ethanol. Rats were injected in the NBM with were bred in our Depamnent for 22 generations from Sardinian alcohol-prefemng either isotonlc saline (IS; controls) or 5 nglsite of NH2-SENK. They received rats of the 13th generation. lntraoral infusion (0.8 mu60 s) of water or ethanol solutions (10, 20, 40 or 60 Water and food sated rats were offered 10% ethanol 2 hrlday, at the beginning of lo) 5 min later. Oral and general motor reactions were recorded. Rats injected the dark phase of an Inverse light-dark cycle. Injections into the medial with NH2-SENK responded to all the ethanol concentrations with pronounced amygdala, CAI region of the h~ppocampus,nucleus accumbens and ventral . . tegmental area at doses up to 50 ngisite were devoid of effect. Administration ingestive reactions, similarly as controls. 2) Into the bed nucleus of the strla terminalis lnh~bitedethanol intake at 5-25 -n (CTA), A CTA paradigm was used to investigate whether NK-3 @site, but the same doses inhibited also food Intake in food deprived rats. receptor agonlsts may influence the aversive effects of ethanol. After a 20 Bilateral Injections of NH2-SENK in the nucleus basal~smagnocellularis (NBM) minlday drinking session of a solution containing 0.125% saccharin and 3% reduced alcohol intake, the threshold dose being 0.5 ngls~te,wh~le ICV injection sucrose, rats were treated with 5 ng/NBM of NH2-SENK or IS, and then of NH2-SENK, 10 nglrat, d~dnot inhibit alcohol intake. On the other hand, injected intraperitoneally (IP) with IS or with ethanol (1 gkg). IP ethanol NH2-SENK, 25 ng/NBM, did not modify water or food intake In water deprived produced a marked CTA that was not modified by NH2-SEm. The NK-3 rats, lnjection in the NBM of the TK NK-3 receptor antagonists, R-820 or S- receptor agonist per se did not evoke CTA. 3) Ethanol metabolism, To 18451, 1000 nglsite, sign~ficantlyreduced the effect of NH2-SENK 5 nglsite. evaluate whether central NK-3 receptors may affect ethanol metabol~sm,blood The selective TK NK-1 receptor agonist [~ar~,~et(~~)~~]substanceP Inhibited alcohol concentration (BAC) was measured in anlmals injected into the lateral alcohol intake only at 25 nglsite. but the same dose induced marked grooming ventricle either with IS [controls) or w~th125 nglrat of MI2-SENK, 5 min and Whited water Intake in water depnved rats. before intragastric administration of ethanol (0.7 gkg). Blood samples were Present results confirm that TK NK-3, but not NK-1, receptor agonists collected 15, 30 and 60 min following ethanol administration. In rats Injected selectively lnh~bitalcohol Intake In alcohol-preferring rats and suggest that the with NH,-SENK BAC were not different from those of controls. Present results NBM is a site of action for their effect. Injection of the TK substance P in the show that NH2-SENK does not modify ethanol taste, averslve effects or NBM evokes conditioned place preference In rats, and increases extracellular metabolism. Studies aimed at Investigating the role of NK-3 receptors In the levels of dopam~neand 5-hydroxy~ndoleaceticacid ~n the nucleus accumbens. reinforcing properties of eth'ulol are in progress. These findings raise the hypothes~sthat stimulation of TKergic mechan~smsin the NBM m~ght.at least in part. substitute for the effects of ethanol. 42 Tuesday, Plenary lectures

CANNABINOIDS ACTIVATE MESOLIMBIC DOPAMINE NEURONS BY AN ACTION ON CBl RECEPTORS GESSA G.L., MELIS M. AND DIANA M. NEUROSCIENCE DEPT. "B.B.BRODIE", UNIVERSITY OF CAGLIARI, ITALY

The present study kas designed to determine ~f cannabinoids share wlth other drugs of abuse the abillty to actlvate mesol~mb~cdopaminerg~c transm~ssion To thls aim, the effects of the prototypical cannabinoid, tetrahydrocannabinol ( THC ), the two h~ghlypotent synthetic cannabinoids WIN 55,212-2 and CP 55,940, and the putat~ve endogenous cannabinoid anandamide on the spontaneous discharge rate of antidromlcally ident~fiedmeso-accumbens dopamine ( AIO-DA ) neurons were studled both In non-anesthetized and chloral hydrate anesthet~zedrats. The I v admin~strationof THC (0.25 - 1.0 mgkg), WIN 55,212-2 (0 0625 -1.0 mgikg) and CP 55,940 (0 25 - 1 0 mgikg) produced a dose-dependent increase in the spontaneous firing of AIO-DA neurons both in non-anesthet~zedand anesthetlzed preparation u,ith a maximal percent increase of 95, 148 and 130 in non-anesthet~zed and 36, 85 and 35 respectively in anesthetlzed rats. In contrast, anandamide up to a dose of 10 mgikg failed to modify AIO-DA neuronal activlty The st~mulantresponse to cannabinoids uas suppressed by the 1.v. administrat~onof the specific cannabinold antagonist SR 141716A but not by naloxone lnd~cating a cannab~no~d-receptormediated effect. The find~ngthat THC shares kith other drugs of abuse the ability to fac~l~tatemesol~mb~c DA transmission suggests that this effect may be relevant to the addictive properties of marijuana. On the other hand the lack of effect of anandam~deon AIO-DA neurons suggests the possib~lltyto develop therapeut~callyuseful cannablno~dsdevoid of addictlve properties. Collectively, the present results indicate that exogenous cannabinoids stimulate mesolimbic dopaminergic neurotransmiss~on by an actlon at CBI receptors In turn. the dopaminergic firing st~mulantproperties of cannab~noidshere reported are reminiscent of those already described for other more harmful substances such as opiates and ethanol Consequently the present results bear not only a scientific value but important polltlcal implicat~ons.

Plenary lectures

Melatonin counteracts necrosis and apoptosis. FUNCTIONS OF OPIOIDS IN THE BRAIN Neville N Osbome Nufield Laboratory of Ophthalmology, University R. Przewloclu of Oxford, Oxford OX2 6AW, [TK Department of Molecular Neuropharmacology, Institute of Introduction: Melotonin is metabolised in the retina and has been Pharmacology, Polish Academy of Sciences, Krakow, Poland implicated in a variety of functions The present studies were undertaken to see if melatonin counteracts ischaemic insults Since primary identification and final cloning of opioid peptide Methods: Experiments were camed out on rat cortical cultures, human retinal pigment epithelial cells and the intact rabbit retina prohormones and receptors, opioid systems have deserved utmost Results: Glutamate and oxygen deprivation stimulated the "release" of attention towards understanding their hnctional roles in the CNS. LDH from rat cortical cultures Inclusion of MK-801 (2pM) or Three independent neuronal oploid systems and multiple receptors melatonin (100pM) in the medium almost completely attenuated the have been identified. These systems are presumed to be involved In effects of glutamate or oxygen deprivation. Ischaemia was delivered to several CNS physiologcal hnctions. Further, they have been the rat retina by elevation of intraocular pressure. After a defined implicated in the pathophysiology of stress, pain, seizures, drug reperfusion time there was a reduction of the b-wave of the addiction and brain injury. It is not clear, however, how the electroretinogram, changes in the distribution of various antigens and endogenous opioid systems contribute to brain pathophysiology, an alteration in the retinal morphology. These changes were clearly and how they adapt themselves and compensate for pathological reduced when the animals were treated with melatonin throughout ischaemidreperfusion stimuli? Recent molecular, biochemical and pharmacological Experimental ischaemia (oxygen and glucose deprivation) resulted in studies into regulatioti of the opioid gene expression, their 80% of the retinal pigment epithelial cell's nuclei staining positively for transcription factors and associated neurotransmitters in DNA fragmentation by the TUNEL procedure. The cells also appeared pathological states permitted us to better understand the role of to shrink, suggesting the process of apoptosis. Inclusion of 10% foetal these opioids in the brain. The obtained data suggest that opioid calf serum or 100pM melatonin attenuated the apoptosis with the cells systems are not hnctionally homogenous and are likely to appearing healthy and not staining positively by the TUNEL method. influence various brain hnctions reciprocally or in opposing ways. Inclusion of MK-801 or luzindole (100pM) did not counteract the Evidence has been accumulated that enkephalinergic and experimentally-induced effect of apoptosis to RPE cells. endorphinergic systems seem to reply to acute neuronal Conclusions: The combined studies show that melatonin can experimentally counteract the effect of insults fhat lead to destruction stimulation and participate in the process of neuroadaptation, while of cells by apoptosis and necrosis. The possibility of elevating the dynorphinergic neurons react to prolonged or repeated stimuli and retinal levels of melatonin to protect against insults such as glaucoma, may contnbute to the development of CNS pathology which lead to damage of retinal neurones, must be considered. Tuesday, Symposial: Neurochemistry and neuropharmacology 43

Oral communications I1 - Neurochemistry and neuropharmacology

Role of NAAG in neurotransmission. B. Wroblewska, S.E. INPOLPEbIENT OF BRAIN DOPAMINE IN CEREBRAL Sullivan, T. Bzdega, and J.H. Neale., Georgetown University. ISCHEMIA AYD NEURONAL DAMAGE IN RAT HEATSTROKE Dept. Biology, Washington D.C., U.S.A. bI.-T. LIN, Department of Physiology, National Yang-hling University, Taipei, Taiwan, R.O.C. N-acetylaspartylglutamate (NAAG) is a dipeptide present in a very The pathophysiology of heatstroke has been ex- high concentrations in the mammalian brain. NAAG meets most tensively studied by many investigators. Its of the traditio?al criteria for a neurotransmitter, however the CNS syndromes include coma, delirium and con- receptor for NAAG, and the role of this neuropeptide in the brain fusion. When exposed animals to a high ambient temperature, the moment at which mean arterial functions are not known. We have shown recently that NAAG pressure began to decrease from its peak level decreases forskolin-stimulated CAMP formation and activates was taken as onset of heatstroke. Heatstroke group I1 metabotropic glutamate receptor(s) in cultured cerebellar was accompanied by hyperthermia, cerebral isc- granule and glial cells. Our data obtained from the cells hemia, neuronal damage, increased brain levels of dopamine, arterial hypotension, and increa- expressing cloned mGluRs indicate that NAAG selectively sed plasma levels of interleukin-1 (IL-1). activates mGluR3 and not mGluRla, 2, 4. 5, and 6. Using Depletion of brain dopamine produced by intra- chimeric molecules (mGluR2-mGluRla and mGluR3-mGluRla cerebral injection of 6-hydroxydopamine was ab- constructs) we were able to show that NAAG interacts with the N- le to attenuate cerebral ischemia, neuronal da- mage and arterial hypotension and to result in terminus of mGluR3 receptor, but not highly homologous extension of survival in rat heatstroke. Also, mGluR2. These data suggested that NAAG, as an agonist of systemic administration of IL-1 receptor anta- metabotropic glutamate receptor (mGluR3) may participate in the gonist was able to attenuate cerebral ischemia, neurotoxic or neuroprotective mechanisms in the brain. Using neuronal damage and arterial hypotension by re- cultured cortical cells (in collaboration with Drs. Bruno and ducing brain dopamine levels. The data indicate that amrked accumulation of brain dopamine re- Nicoletti. Univ. of Catania) we were able to show that NAAG sulting from increased plasma levels of IL-1 protects neuronal cells from NMDA-induced neurotoxicity, and may be an important mechanism signaling cere- this protective effects are mediated through the glial cells. We bral ischemia, neuronal damage and arterial hy- have also recently cloned, sequenced and expressed the full length potension in heatstroke. rat hippocampal cDNA encoding for NAAG peptidase - an enzyme which cleaves NAAG to N-acetylaspartate and glutamate. The RT-PCR screening indicates the presence of the message encoding NAAG peptidase in rat brain. kidneys and spinal cord.

INFECTION AS A STRESSOR: THE ROLE OF CYTOKINES Effect of tachvkinlns on the central res~iratorvact~vitv: an In vitro studv on the Adrian J. Dunn newborn rat Department of Pharmacology and Therapeutics, Louisiana State Krzysztof ~tak~,~,Roger Monteaua, Gtrard Hllalrea University Medical Center, Shreveport, LA, USA aLaborato~rede Biolog~edes Rythmes et du Developpement, URA CNRS 1832, Faculte des Sciences St J&r6me,13397 Marse~lle,France Stress is associated with an activation of peripheral and central b~akladFizjologii Zw~erzat,Instytut zoo log^^ UJ. ul. Ingardena 6, 30-060 catecholaminergic systems and the hypothalamo-pituitary- Krakow. Poland adrenocortical (HPA) axis. In the brain, stress is associated with activations of noradrenaline (NA) and CRF. Animal studies suggest Tachylunins are a family of neuromodulators among wh~chsubstance P activation of dopaminergic and serotonin (5-HT) systems, as well as (SP) &as the first to be ev~denced.In the 1980s, neurok~n~nA and neurokinin B elevations of free tryptophan (Trp). It has been shown that infections were also ~solated.Three types of receptors (NK], NK2 and NK3) med~atethe and other treatments known to activate the immune system (e.g., effects of tachykinins. SP displays a tugher aff~n~tyfor tachyk~ninNKI receptor. endotoxin) cause activation of the HPA axis, as well as NA, Trp and Several results have suggested that substance P might be ~nvolvedin the 5-HT in the brain, and some sympathoadrenal activation. Thus by respiratory regulation In mammals physiological criteria these treatments are stressful. There are also The alm of the present work was to Investigate the effects of tachykinins, parallels between the behavioral consequences of stress and infection: particularly SP, on the act~vityof the respiratory rhythm generator In the hypomotility, hypophagia, decreased exploration and libido and ne~bornrat and to determine the type of the tachykinin receptors ~nvolved. increased sleep time. Injection of cytokines, such as interleukin-1 Exper~mentswere performed uslng newborn rat (0-3 days old) brainstem- spinal cord preparation ~hich&as placed in a chamber permanently perfused (IL-l), IL-6 and tumor necrosis factor a (TNFa ) secreted early in w~thartificial cerebro-spinal fluid (aCSF). Substance P and pharmacolog~cal immune responses, activate the HPA axis. L-1 activates NA agents acting as tachykinin receptor agonlsts or antagonlsts were d~ssolvedIn systems, and IL-1 and IL-6 increase brain Trp and activate 5-HT, but the aCSF and applied by superfusion at several concentration (10-lo - IO-~M). TNFa induces no effects on NA or 5-HT. IL-I can elicit the whole Substance P and tachykinin NKI and NKj agonlsts Induced a concentration- spectrum of infection-related responses, including fever and the dependent increase In the resplratory frequency (10.~- IO-~M),&hereas the behavioral responses. Thus these cytohnes may be mediators of the resplratory frequency &as only sl~ghtlyaffected by tachyklnin NKl receptor responses to infections and immune challenges. Cytohne antagonists, agonlst. Pre-treatments w~thtachykin~n NKI receptor antagonists reduced the such as the IL-1-receptor antagonist (IL-lra) have failed to substance P-induced increase In the resplratory frequency but the tachykin~n demonstrate that IL-1 is the predominant mediator of the HPA, NK? receptor antagonlsts had no effect. The increase in the respiratory neurochemical and behavioral responses to LPS, although some frequency induced by the tachykinin NK3 receptor agomst was not affected by a attenuations of IL-Ira on the HPA response and on ingestive behavior pre-treatment with tachykin~nNKI and NK2 receptor agonists. are observed. A monoclonal antibody to IL-6 partially attenuated the The results indicate that substance P may exert potent fac~l~tatoryeffects on HPA responses to LPS and IL- 1. Antibodies to TNFa were the respiratory rhythm generator and that tachyk~ninNKI and NKj receptors inneffective. These results suggest that cytokines may participate in may be involved In the control of the respiratory frequency the physiological and behavioral responses to infections, but that other factors are also involved. 44 Tuesday, Symposial: Neurochemistry and neuropharmacology

NlFEDlPlNE MODULATES SOME CHANGES INDUCED BY ANTIDE- NEW ANTAGONISTS OF THE 5-HTIARECEPTOR PRESSANTS IN ADRENERGIC TRANSMISSION AT THE SECOND Zdzislaw Chilmonczyk, Agnieszka Szelejewska-Woiniakowska, MESSENGERS LEVEL Jacek Cybulski, Ewa Chojnacka-Wojcik* I. Nale~a.G. Kreiner, M. Kowalska, J. Vetulani, Institute of Pharmacology. Polish Academy of Sciences, 31.343 Krakow, Poland Pharmaceutical Research Institute, Rydygiera 8,Ol-793 Warszawa. Antidepressant therapies produce long-lasting adaptive changes in the *Institute of Pharmacology, Polish Academy of Sciences, Smqtna brain, possibly associated with intracellular Ca2+.Here we investigated the 12, 3 1-343 Krak6w. effect of Ca2'-channel blockade (CCB) on the changes induced by chronic antidepressant treatments: imipramine (IMI) and electroconvulsive shock Several new analogues of buspirone, a known anxiolytic drug, were (ECS), in the responses of second messenger systems linked with a,- obtained. The compounds exhibited high affinity to 5-HTIAreceptor and (3-adrenoceptors (AR) and the protein kinase C (PKC)-inducedpoten- and were examined in the lower lip retraction and the 8-OH-DPAT tialization of the (3-AR response in the brain cortex. Wistar rats received induced hypothermia tests, evaluating post- and pre- synaptic, ECS (150 mA, 250 ms) for 10 days or IMI (10 mglkg, i.p., b.i.d.)for 21 days, each shock or injection being preceded 15 min earlier by solvent or respectively, activity of the receptor ligands. It appeared that some the Ca2*-channelblocker nifedipine (NIF),5 mglkg. 24 h afier the last compounds were able to reverse the 8-OH-DPAT induced lip treatment the rats were killed and inositol phosphates (IP) response to retraction in rats in similar doses as known antagonist of the receptor norepinephrine (NE) (an a,-AR response) and cyclic AMP (CAMP) (S)-WAY 100135: mesmar - 4.0, kaspar - 6.1, A-1 - 8.0, (S)-WAY response to NE and isoproterenol (a 13-AR response) in the presence and 100135 - 6.0 (ED5o mgkg). Mesmar and A-1 in a dose 10 mgkg, absence of a PKC activator, TPA, was measured in the cortical slices. The chronic intermittent CCB with NIF did not affect the responsiveness similarly to (S)-WAY i00135 (10 mgkg), completely reversed of cerebral cortical a,-AR. Neither IMI nor ECS treatment changed the 8-OH-DPAT induced hypothermia in mice. Mesmar and A-1 thus responsiveness of a,-AR in naive rats, but when given under CCB they behaved like functional antagonists at both pre- and postsynaptic caused an increase in the IP response to NE. Similarly, administration of S-HTIAsites. NIF alone induced no change in the responsiveness of (3-AR, but given during CCB imipramine and ECS, the treatments that down regulate the (3-adrenergic system, produced different efects. ECS that normally did not affect the cAMP response to isoproterenol in the presence of TPA, under condition of CCB down regulated it. IMI, which normally blocks the TPA- potentiation of cAMP response, did not produce that effect when administered afier NIF. Thus, the chronic changes in the AR systems induced by chronic antidepressant treatments (both in responsiveness of receptor systems and the receptor crosstalk) may be changed when anti- depressants are given when Ca2+channels are blocked. The importance of this finding lies in the fact that several depressed patients are also treated for circulatory disturbances, and Ca2'-channel blockers are frequently used cardiac drugs.

PROLONGED CORTICOSTERONE TREATMENT ALTERS BIOCHEMICAL AND FUNCTIONAL PARAMETERS OF SEROTONERGIC NEUROTRANSMISSION ASSOCIATED WITH 5-HTlA RECEPTORS A ~~~fal.kou~ak,K fijab A Chocvk, K TokarsXi, M Bijak and K. C~dzony. Institute of Pharmacologv, Polish Academv of Sciences, 31-343 Krakow, Smetna Sheet 12, Poland The aim of the present study was to investigate the impact of repeated administration of corticosterone (10 mgkg, twice daily, for 7 days) on biochemical, behavioural and electrophysiological parameters characteristic of the 5-HT neurotransmission associated with 5-HTlA receptors. It was found that prolonged treatment with corticosterone increased the number of 5-HTIA receptors in the raphe nuclei, prefrontal cortex and hippocampus, as measured by quantitative autoradiography and saturation binding in brain homogenates using [3~8-~~-~~~~as a ligand. The level of 5-HT in raphe nuclei was not changed by corticosterone, whereas the level of its metabolite 5-HIAA was increased. In the prefrontal cortex and hippocampus the levels of both 5- HT and 5-HIAA were increased alter chronic corticosterone treatment. On the other hand, we observed that chronic corticosterone attenuated the 8-OH-DPAT evoked disruption of the prepulse-induced inhibition of acoustic startle response and decreased the 8-OH-DPAT-induced inhibition of a population spike and hyperpolarization in CAI hippocampal neurons. Both these effects indicate that chronic corticosterone decreased the functional responsiveness to stimulation of 5-HTlA receptors. It is concluded that chronic occupation of glucocorticoid receptors by corticosterone increases the density of 5- HTIAreceptors and 5-HT turnover In contrast to the effects observed in binding studies, corticosterone attenuates most of the functional effects induced by 5-HTIAreceptor stimulation Tuesday, Symposial: Development and plasticity 45

Symposial 3 - Development and plasticity of sensory systems

A COMPARATIVE SURVEY OF THE ORGANIZATION OF Sensory stimulation of gene expression in neuronal plasticity SOMATOSENSORY NEOCORTEX IN MARSUPIALS. K Huffman, Kaczmarek L. J. Nelson. M Sum & L. Krubitrer. Center for Neurosc~ence. Unlverslty of Nencki Institute, 02-093 Warsaw, Pasteura 3, Poland California. Da~ls.CA. USA Th~slnvest~gatlon IS part of a broader effort to determine features of neocortlcal organuatlon that are com~nonto all mammals, and features that xose An involvement of gene expression in neuronal plasticity has Independently In d~fferentllneages The marsupials we have studied Include the been well documented. The components of the @-1 transcriotion AustralIan dunnart (Str~rrirhoprls crmr~cairdntira).quoll (Dasjurirs hall~~cat~~s).and factor (in particular, c-Fos) and Zif268 have been especially atnped possum (Drrcnlops~/atrlvrrgata), and the South Amerlcan short-talled widely investigated in this regard. However, the roles of these two possum (Monodeipi~isdortrest~ca) In the quoll, strlped posaum. and ahon-ta~led possum. the reglon of conex responslbe to atlmulatlon of somatic receptors uas proteins in neurons remain speculative and include such varied explored uslng multlunlt electrophys~olog~calrecordlng techniques. Receptive functions as short-term maintenance of cellular homeostasis to tields for neurons at mult~ple, densely spaced recordlng altes were obtained, and long-term changes that guide neuronal plasticity. Current efforts at cortlcal field boundmes were determined by examining reversals In receptlbe field elucidating the physiological roles of AP-1 and Zif268 rely on progreaslons. changea In neural reaponse propenles. and st~muluspreferences. In assessing their expression in response to different conditions of all specles, cortex waa flattened. cut parallel to the conlcal surface. stalned for myelln, and reacted for cytochrome oxldase (CO). The arch~tectonicd~stlnctlons behavioral, sensory and pharmacological stimulation. In our apparent in hlstologlcally processed tlssue were conelated w~ththe cortlcal field studies, we have examined the expression patterns of these boundarlea establ~shedfrom electrophys~ologlcalrecordlng results. In the dunnart, transcription factors in the mammalian sensory cortex under only myeloarchltectonlc boundaries were ascenalned. In all specles. at least three different conditions, with particular emphasis on the constitutive dlstlnct fields could be ~dentlfied. The prlmary somatosensory xea, SI. uas levels and how they change after sensory deprivation, stimulation characterired by a complete topographic representatlon of the body surface coextensl~ewlth a darkly myellnated. CO denae area. Neurons in SI responded to and behavioral training A synthesis of this information implies stlmulatlon of cutaneous receptors. A moderately myelinated field immediately that whereas expression of Zif268 appears to reflect ongoing rostral to SI, termed the rostral deep area, R, also contamed a complete synaptic activity, and thus the protein may be involved in representatlon of the body surface. Howe~er,neurons In thls field responded to maintenance of neuronal function, the expression pattern of c-Fos atlmulatlon of deep receptor\. Flnally, in conex lmmedlately lateral to SI, a amall, moderately myelinated reglon which was contiguous with another complete (or to be more precise AP-1 containing c-Fos) could be explained representatlon of the body surface waa ternied SIIIPV. Although basic features of by either replenrshment or informairon integraiion approaches to anmatosensory cortex were slmllar acrosa these specles of marsuplals, the Internal understand the role of gene expression in neuronal plasticity. organlrat~ondlffered drarnatlcally In SI, anl~nalstended to have varylng a~nounts (if cortex devoted to thelr different morphological speclallzations Alao. the expanuon of neoconex across these speclea was nonlinear with respect to body slze, and uas especially exaggerated In the stnped possum. This expansion is poaslbly a result of the complex behawor patterns and social Intevactlons that thls specles exhlblts.

ORIGINSOF MODIFICATIONS OF CIRCUITRY WITHIN THE RAT S1 MORPHOLOGICAL AND FUNCTIONAL REORGANIZATION BARRELCORTEX SUBSEQUENT T o CHANGESI N TACTILE IN THE VISUAL SYSTEM AFTER TREATMENT OF THE EXPERIENCE. DEVELOPING RETINA WITH APB S. Bisti. S. Deplano, C. Gargini, L.M. Chalupa. Michael Armstrong-James Dept. STBB, Univ. L'Aquila; Univ. Genova; 1st. Policattedra DEPARTMENTOF PHYSIOLOGY, BASICMEDICAL SCIENCES, Discipline Biologiche, Univ. Pisa; 1st. di Neurofisiologia C.N.R., QUEENMARY AND WESTFIELDCOLLEGE, LONDONUNIVERSITY, Pisa, Italy; Sect. Neurobiol. Physiol. &Behavior, UC Davis 95616, MILEEND, LONDONE14NS USA. The gradual restriction of initially multistratified ganglion cell When somatosensory experience is changed in the dendrites into ON and OFF sublaminae of the IPL can be arrested adult mammal. then modifications of both thalamic. by treating the developing retina with APB, the metabotropic thalamocortical and intracortical synaptic relays may contribute to receptive field plasticity of S1 glutamate agonist (Bodnarenko & Chalupa, Nature, 1992: Bodnarenko et al. J. Neurosci., 1995). To assess the possible cortex. We have investigated these separate aspects of reorganisation within the barrel cortex and the functional consequences of such treatment, cats were administered somatosensory (barreloid) thalamus of adult rats a daily injection of APB from P3 until P30, with a 2 day respite on following 3 to 30 days of cutting all whiskers except week-ends. When the animals were at least 3-months of age, two being cut unilaterally. Modifications to paired extracellular recordings were made from the A and A1 laminae of and unpaired (cut-Whisker) inputs occur at thalamic the dLGN and receptive field properties were examined using as well as cortical levels. Both Hebbian and anti- computer-controlled stimulus presentations. In the dLGN layers Hebbian modifications occur. Statistical analyses of innervated by the normal eye, all cells responded to small spots of changes in spatio-temporal features of responses in light centered on the receptive field with either ON or OFF homologous barrel and barreloid neuronal discharges. In marked contrast, about 40% of the cells in the layer populations suggest that the use-dependent innervated by the APB-treated eye responded to such stimuli with alterations in the thalamic relay contribute probably ON-OFF discharges. Such responses were elicited from all regions contribute little to alterations in processing of of the receptive field. At the end of the recording session, retinal sensory information at the cortical level. These ganglion cells were filled with HRP and both control and treated features will be elaborated and their relevance to retinae were analyzed. Our results show, that the incidence of ON- models for use-dependent reorganisation of sensory OFF cells was nearly identical to the proportion of ganglion cells processing in the somatosensory system will be with multistratified dendrites in the APB-treated retinas. discussed. Supported by the Welcome Trust (U.K.) and the NIH (USA) 46 Tuesday, Symposial: Molecular aspects . .

ELIMINATION OF CALLOSAL AND CLAUSTRAL PROJECTIONS TO CORTICAL AREAS 17 AND 18 IN CATS WITH NEONATAL SEROTONERGIC LESION. Turlejski K. and Djavadian R. Nencki Institute of Experimental Biology, 3 Pasteur st., 02-093 Warsaw, Poland. We studied the influence of serotonin depletion on the process of developmental ellmination of callosal axons. Experimental kittens were injected on the first two postnatal days with desipramine and one hour later with 5,7-dihydroxytryptamine. At the age of three months injections of Fast Blue were done into the cortical areas 17 and 18 of one hemisphere in the experimental and normal cats. In the normal animals callosaly projecting neurons were limited to the transient zone of area 17/18 and the part of area 18 representing visual field up to 10-15 deg from the vertical meridian. In the group of serotonin depleted cats callosal connections of visual areas were largely expanded. Besides of the 17/18 transient zone, they covered the representation of 5-10 deg from the vertical meridian in the area 17 and almost all of the area 18. Claustrum was another structure that changed pattern of projection after serotonin lesion. In the ipsilateral claustrum of the serotonin depleted cats total number of the labelled neurons was increased by 30-50%, while in the contralateral claustrum the labelled neurons were 2-3 times more numerous. These results show that depletion of serotonin disturbs and decreases the retrograde process of partial elimination of excessive projections that finally shapes the cortical connections. Supported by grant KBN 4P05A 081.11

Symposial 4 - Molecular aspects of physiological and pathological aging in the brain

Dietary manipulation which restores the age-related decrease in membrane RECEPTOR MEDIATED SECOND MESSENGERS FORMATION AND arachidonic acid in rat hippocampus reverses some age-related impairments in FUNCTION IN AGED BRAIN. MODULATORY EFFECT OF AMYLOID P synaptic function. PEPTIDES. JOANNA STROSZNAJDER, M SAMOCHOCKI, M CHALlMONlUK MA Lynch, B McGahon and C. Murray, Department of Phtsiology, Trinity Department of Celiular Signalling, Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego Street, 02-106 Warsaw, Poland. College. Dublin 2. Ireland. A varlety of neurotransmitters, hormones, growth factors and constituents of the extracellular matrix cause a stimulation of phosphoinos~tidesand hydrolys~s Ageing is accompanied by a number of changes in synaptic function in rat of hosphatidylchol~neby phosphollpases C, D and A2 GTP-binding proteins, hippocampus. These changes include an impairment in ability of aged Cak'+ Ions and protein k~nasesare ~nvolvedIn the receptor -mediated regulation animals to sustain long-term potentiation (LTP) in the dentate gyms, which of these enzymes The substrates and products of phospholipases play a correlates with a decrease in glutamate release. Data from several significant role In s~gnaltrasductlon, veslcle flow and trafficking The second expenments have indicated that LTP is accompanied by a persistent increase messengers produced by phospholipase C (PLC) and PL42, inosltoi 1,4,5- trisphosphate (Ips), arachidonic acid (AA) and phosphat~d~cacld, the maln in glutamate release; evidence suggests that the increase in glutamate release med~ator produced by phospholipase D (PLD) have been implicated in relies on coincident stimulation of phospholipase CP (PLCP) and PLCy by the regulation of cytosolic ca2+ concentration and mechanisms of learning and metabatropic glutamate receptor agonist, ACPD, and arachidonic acid memory We observed that brain aging significantly and selectively decreases respectively. We have found that this interaction is impaired in aged animals. receptor mediated, Ips dependent ca2' mobilisatlon and arachidonic acid Although the underlying cause of these age-related changes is not known. it release and enhances phosphatldlc acid formation In bra~n cortex has been speculated that the decreased membrane arachidonic acid Phosphatidyl~nositol transfer prote~ns, that has been impl~catedto play an essential role In PLC-mediated phosphat~dylinositoi-4,5-bisphosphate (PIP>) concentration. which contributes to increased membrane rigidity, may play a hydrolysis, as well as In membrane fusion and budd~ng processes were not role. This hypothesis predicts that if membrane fluidity is restored in aged affected during brain aging In spite of alteration of lipld derlved second animals. then the age-related changes in synaptic function should be reversed. messengers, aglng dim~nishedNMDA-receptor mediated NO dependet cGMP Evidence will be presented which indicates that dietary supplementation with formation In hlppocampus and cerebellum. Our in vitro studles on the actlon of arachidonic acid and gammalinolenic acid restores membrane arachidonic amylo~dp pept~des(Ap25-35, Apl-28 and Apl-40) on chol~nergicand NMDA acid concentration in 22 month-old rats to values observed 4 month-old rats receptor mediated second messengers system showed a significant modulat~on and that this change is accompanied by a reversal of the age-related (1) of Ips, AA and cGMP dependent processes, involved In regulat~onof ca2+ impairment in ability to sustain LTP, (2) decrease in glutamate release and (3) homeostasis These results suggest that amylo~d p may be ~nvolved In alteration of neurotransmission and signal transduction processes In aged the compromised release response to ACPD and arachidonic acid. The brain. The recent cloning of eucariotic phospholipases and NO synthase genes, possibility that increased expression of the proinflammatory cytokine, also from human sources uncovered a novel gene family, whose members may interleukin-113, may contribute to some of the age-related impairments in be lnvolved In varlous aspect of slgnal trasductlon and membrane traffickrng hippocampal function will be discussed. These new findings will be helpful for the better understanding of aged reiated alterations occurlng In brain Tuesday, Symposial: Molecular aspects . . .47

POSSIBLE ROLE OF POLY(ADP-RIB0SE)SYNTHETASE IN HB-GAM IS A NOVEL AMYLOID ASSOCIATED PROTEIN IN CEREBRAL AMYLOIDOSES. NEURONAL DEGENERATION Mac~e]M ~alowsk~'#,M Baumann3 H ~auvala' B ~rangione~Thomas Wlsnlewsk15 '~edlcalResearch Centre Pollsh Academy of Sclence Warsaw Poland 2~epartmentsof Kunihiro Ueda, Institute for Chemical research, Kyoto University, Pathology and '~eurolo~~NYU Med~calCenter USA ' lnstltute of Blomedlclne and ' Institute Kyoto, Japan of Biotechnology Unlverslty of Helslnkl Flnland (# macleiCf~bbra~n~bb waw PI) Poly(ADP-ribose) synthetase (PARS) (also termed polymerase; HB-GAM (heparin blndlng growth assoc~atedmolecule) was recently described as a novel amylo~dassoc~ated protein In amylold p (Ap) cerebral amyloldoses of Alzhelrner s dlsease PARP)is a nuclear enzyme that catalyzes formation of protein-bounce and Downs syndrome Antibodies to HB-GAM immunolabelled both neurltic and dlffuse (ADP-nbose), (n=2 - loo<) from NAD'. PARS is composed of three (preamyloid) plaques only when markers of neuronal Injury were present as well as a subset of functional cominess, i.e. DNA binding(N-thermal), automodification neurons contalnlng abnormally phosphorylated tau ep~topes(1) It was suggested that HB-GAM IS one of the co- factors assoclated wlth the cerebral plaques of Ap and acts as a marker of (central), and catalytic (C-terminal). The enzyme activlty is markedly neuronal ~njuryTo explore the role of HB-GAM In other cerebral and systemlc amylo~dosesas stimulated by damaged DNA. well as ~tsrole as a marker of neuronal Injury we performed lmrnunohlstochemical studles wlth Although the precise functions of PARS remain to be elucidated, anti- HB-GAM antlbodles In 3 cases of Creutzfeld- Jakob d~sease(CJD) one wlth Gerstmann- there 1s accumulating evidence suggesting its roles In DNA repair, Straussler- Schelnker syndrome (GSS) one wlth amyloidosls of Brltlsh type 1 case of novel men~ngocerebrovascular amylo~dosts of Hungarian type 3 cases of hereditary cerebral genome surveillance, and cell differentiation. Furthermore, PARS has haemorrhage wlth amylo~dosls-Dutch type 3 cases wlth llght chain deposltlon and one case of been identified as a substrate of ICE-like protease ("caspases") in gelsolin related amyloldosis It was found lmmunohlstochemlcally that HB-GAM is a co- factor apoptosis. We recently found that PARS is phosphorylated by associated wlth cerebral amylold deposition both in parenchymal and vessel arnyloid lesions It DNA-dependent protein kinase in apoptotic lymphocytes and that the was absent in the systemlc arnylo~ddeposlts which we tested The presence of HB-GAM correlated well wlth the presence of other amylo~dassoclated protelns apol~poprotelnsE and J phosphorylation accelerates the cleavage of PARS at a slte within the and proteoglycans In the cerebral amylo~ddeposlts In order to establish a role of HB-GAM as a nuclear localization signal. The subsequent loose of nuclear PARS marker of neuronal Injury In certaln braln reglons after lschemlc insult we also started would hberate endonuclease(s) from suppression by (ADP-ribose)n and prellmlnary studles using Western blotting wlth antl- HB-GAM antlbodles and dens~tometr~c lead to nucleosomal DNA strand breaks, a hallmark of apoptosis. analysls on homogenates from dlfferent regions of the rat braln To further explore the role of HB-GAM In amylold deposltlon we performed in vitro studles with Ap synthetic peptldes These Activation and cleavage of PARS were also observed in neuronal cells in vitro studies showed that HB-GAM can form a hlgh afflnlty complex wlth several Ap peptides exposed to ionizing radiation, respect~vely. wlth a b~ndingconstant KD= 12 1 nM for Apl-40 KD= 13 0 nM for Apl-28 and KD= 22 1 nM These results suggest that the functional PARS IS essential for for AD1 42 The complex was concentratlon dependent and partially reslstant to SDS as survival of neuronal cells under variously stressed conditions and its evldenced after Laemml electrophores~sof the preformed complex and Western blotting analysls usng ant- Ap and ant- HB-GAM antlbod~es HB-GAM was also able 3-4 fold to degradation may serve for neurodegeneration. increase the rate of f~brllogenes~sof Apl-40 as evldenced by uslng Thioflavln T method We suggest here that HB-GAM IS more speclflc than many other amyloid assoclated proteins as we have found ~tsdlstrlbution to be llmlted to cerebral deposlts HB-GAM may Influence amyloldogenes~sby the formation of hlgh afflnity complexes wlth amylold peptldes We suggest here that In add~t~onto ~tsknown properties as a neurlte- outgrowth promoter HB-GAM has a role a local tlssue factor assoc~atedwlth cerebral amylo~ddeposlts 1 Wlsnlewski et al Neurorepon (1996) 7 667-671 Supported by NIH grants NS 30455 and AG 08721 Sandoz Foundation for Gerontological Research grant and State cornmitee for Sclentlflc Research grant (4 P05A 020 11) to M L M L 1s a recipient of Foundation for Polish Sclence grant

APOLIPOPROTEIN E AND DEMENTIA HANNA WEHR INSTITUTE OF PSYCHIATRY AND NEUROLOGY ul. Sobieshego 119 02 957 WARSAW POLAND

,Human apolipoprotein E (apo E) is synthesized in various organs including the brain. It is a component of plasma lipoproteins serving as a ligand for cell receptors and participates In lipid transport. It .plavs . also a role in cholesterol redistribution among cells and has an important function in the regeneration of nerves. Apo E is polymorphic and appears in three isoforms named 2, 3 and 4 differing from each other by a single amino acid substitution and coded by three alleles at a single gene locus. The most common isoform is apo E3. Carrying a particular apoE isoform has an influence on plasma lipid level of an individual. It was stated that apoE is a component of Alzheimer plaques and neurofibrillary tangles accompanying amyloid depositions. It was also observed that in patients with late onset Alzheimer disease apo E4 isoform is more frequent as compared with general population. On the contrary, it appears that apo E2 isoform is inhibiting the onset of Alzheimer pathology. Apo E4 frequency in other types of dementia is still controversial. Studies on possible mechanisms of particular apo E isoforms contribution in the development of dementia proceed into several directions. Investigations concern their binding with amyloid, their modulation of neurite extension. their interaction with microtubule associated protein. 48 Tuesday, Poster session: Development

Poster session - Development

CALCIUM-BINDING PROTEINS IN THE MATURATION OF SYNAPTOPHYSIN IMMUNOREACTIVITY IN THE THE RAT BASOLATERAL AMYGDALA BASOLATERAL AMYGDALA AND HIPPOCAMPUS Janusz MOTS, Boiena Berdel, Beata Maciejewska. Olgierd Narkiewicz DURING THE MATURATION Department of Anatomy and Neurobiology, Medical University of Gdansk, Bozena Berdel, Janusz MoryS, Beata Maciejewska, Olgierd Narkiewicz Gdansk, Poland Department of Anatomy and Neurobiology, Medical University of Gdansk, Gdansk, Poland In different species the basolateral amygdaloid complex consists of nuclei which have different cpo- and chemoarchitectoniccharacteristics. The function of this complex includes Synaptophysin is an integral membrane protein associated with small, electron- the emotional, motivational and memory processes. lucent synaptic vesicles. lmmunohistochemistry for synaptophysin is a sensitive The present study IS a part of an ongoing study aimed at elucidating the morphology of the amygdalar nuclel during the maturation and. in particular, the distr~butionof different method to study subtle changes in synaptic density and their distribution in various populat~onof inhib~toryneurons. Studies of other authors have shown that about 20?'0 of brain regions. neurons In the basolateral complex are GABAergic. These cells are composed of different In the present study, the synaptogenesis was examined in the rat basolateral subpopulat~onsof neurons which contain e~thercalb~ndin-D28k or pawalbumin. In the amygdala in comparison to the hippocampus. tiom the day of birth to adulthood. A present study. we describe the distribution of cells. fibers and terminals that ye total of 40 brains at various ages starting from PO to P60 were examined. Care and imiunoreactlve either to parvalbumin or calbindin D28k in the basolateral complex during treatment of the animals were in accordance with the guidelines for laboratory the maturation of the brain. animals established by the National Institute of Health as well as by the local ethical A total of 40 brains of animals at various ages starting from PO to P60 were available in committee. After perfusional fixation the brains were frozen and cut on the Jung this study for ~mmunohistochemicalanalysis. Care and treatment of the animals were in accordance wlth the gu~delinesfor laboratory animals established by the National Institute of cryostat 1800 in the coronal plane and stained either with cresyl violet or standard Health as well as by the local ethical committee After petfusional fixation the brains were immunohistochemical methods using the anti-synaptophysin antibody. frozen and cut on the Jung cryostat 1800 in the coronal plane. and sta~nedeither with cresyl Synaptophysin positive gr&ules appeared just after birth in both structures, but violet or standard imiunohistochemical methods. using the anti-parvalbumin and anti- their number was very low (about 0,18 x 1o6 and 0,19 x 1o6 per mm' in the calb~ndinD-28k antibody. amygdala and hippocampus respectively). In the basolateral amygdala the number Calbindin posltive cells appeared just after birth and reached the maximum of density at P5 of synapses increased up to 1,4 x 1o6 per mm' at P 14 being later stabile. In the in the basolateral nucleus and at P21 in the lateral nucleus. The pawalbumin positive cells hippocampus two increases of the synaptogenesis were observed. The first at P7 are present slnce PI7 in the lateral nucleus and since P30 in the basolateral nucleus with the (about 1.9 x lo6 of synapses per 1 mm') which was followed by dramatic decrease maximum peak at P21 and P30 respectively. During that time staining of both tpes of up to 0,7 x lo6per mm' at P14. The second increase appeared later (about P90) and immunopositive cells became more intensive and dendritic arbor enlarged. The process of maturation ended at P90 when the immunoposltive neurons showed long, ramified dendrites, reached 2.1 x lo6 per mm'). After that time the density of synapse was stabile. especially for pawalbumin-positive cells; at that time the pawalbumin-immunoreactive It may be supposed that the first characteristic wave of synaptogenesis observed in varicose fibers and axon terminals were present around the unstained neurons and formed the hippocampus is due to the overproduction of synapses observed at that time in basket-like plexi and cartridges. other cortical regions. The second wave of synaptogenesis found both in the The distr~butionof the calcium-bmdingproteins in the basolateral complex during the hippocampus and amygdala is related to the great plasticity of the interneuronal maturation has not been described yet. Therefore. this study may provide. basic information connections in this period of development. to study the develop~iientof organization of GABAergic inhibitory circuitries ~nthe amygdala.

POSTNATAL DEVELOPMENT OF THE RAT CAUDATE- THE INSULAR AND PREPIRIFORM PARTS OF THE RAT PUTAMEN - A STUDY USING IN SZTU DNA END LABELING CLAUSTRUM SHOW DIFFERENT PATHS OF TECHNIQUES DEVELOPMENT Maigorzata Lipowska, Beata Maciejewska, Janusz MoryS, Bozena Berdel, Beata Maciejewska, Bozena Berdel, Janusz MoryS, Olgierd Narkiewicz Olgierd Narkiewicz Department of Anatomy and Neurobiology, Medical University of Gdansk, Department of Anatomy and Neurobiology, Medical University of Gdansk, Gdai~sk,Poland. Gdansk. Poland. The claustrum is an important, telencephal~cstructure. It is composed of two clearly Caudate-putamen (dorsal striatum) is a part of the rat striatum which receives separated parts: the dorsal - insular claustmm and the ventral one - prepirifomi claustmm. inputs mainly tiom the neocortex and substantia nigra. It is well knom that in many As the development of both parts of the claustmm 1s still a matter of dlscuss~on,we tried to find similarities and differences in their development and maturation using morphometrlc regions of the brain a large number of neurons die during the development and and m sltu DNA end labeling (TUNEL)methods. maturation, however. we have no data about this process in the caudate-putamen. 45 rat brains of various ages (embryonic days: E15. E17. E21, postembrion~cdays PO, Morphological evidence of apoptotic cell death include cell shrinkage, condensation P1, P2. P4, P5, P7, P8, P10, P21, P60, P90, P180) were studied. Care and treatment of the of nuclear chromatin and appearance of apoptotic bodies. At the biochemical level, animals were in accordance with the guidelines for laboratory an~malsestablished by the apoptosis is attended by DNA fragmentation, which can be detected using in situ National Institute of Health as well as by the local ethical committee All the an~malswere DNA end labeling technique (TUNEL method). decap~tatedunder general anesthesia; after perfusional fixation their bra~nswere removed In the current study we calculated the number of apoptotic cells during postnatal and placed in formalin solution. 10-pm-thick paraEn, serial sections were cut and sta~ned maturation of the caudate-putamen using either cresyl violet staining or TUNEL with cresyl violet or were studied by using the in situ specific labeling of fragmented DNA method. (TUNEL method). Quantitative estimations of the neuronal cells population of the claustmm 27 rat brains of various ages (postembrionic days: PO, PI, P2. P4, P5. P7, P8, were performed using the morphometric methods. On about 20th day of prenatal life the rat's claustmm is visible as a separate structure; P9. PIO) were studied. Care and treatment of the animals were in accordance with the morphology of neurons in the insular part of this structure shows that they are less mature the guidelines for laboratory animals established by the National Institute of Health than neurons in the prepiriform one. Between E20 and P21, a rapid decrease of neuronal as well as by the local ethical committee. All animals were decapitated under density, increase of cross-sectional area of neurons, and their nuclei and Increase of volume general anesthesia, after perfusion fixation, their brains were removed and placed in of the insular and prepiriform claustrum were observed. According to our results, formalin solution. IO-p-thick paraffin, serial sections were cut and stained with morphological features of the claustrum and its neurons do not change after 3rd week of cresyl violet or TUNEL method. ooshlatal life - neurons of both oarts achieve momholoeical, - maturitv As at staee E20. the We found that the postnatal development of rat caudate-putamen is related to insular part of the claustmm is less mature than the prepiriform one, we may assume that the massive physiological death of their neurons. The greatest number of TUNEL- dynamics of morphological changes during the development is higher In the insular claustmm. positive and pyknotic cells per section were observed in this structure during the Onl\ In the Insular zla~strum\re founJ 3 30.0 dt:rcasc In thc tot.i! nu~nheroi neuror:s first week of the postnatal life (from about 40 TUNEL-positive cells per section at Jurlne the se~ondweel, of l~fcIhe loss of these neur.mr. :onfirmed h\ the IT.'\T1 ~ncrhuJ. PI to 28 Tb'NEL-positive cells at P7): later a decrease in number of apoptotic cells was caused by the physiological death. was observed (about 5 TUNEL-positive cells per section at P10). According to our results, the development of the insular and prepiriform claustrum shows The appearance of phys~ologicalcell death during the development of the striking differences which are probably based on specific functions and connections of each caudate putamen is probably a consequence of the elimination of neurons that have These differences are expressed by higher dynamics of development and the occurrence of failed to receive ..appropriate" neocortical and nigral afferents. physiological neuronal death in the insular. phylogenet~callyyounger part of th~sstructure. Tuesday, Poster session: Development 49

PARVALBUMIN IMMUNOREACTIVITY IN THE DOES THE VOLUME OF THE CLAUSTRUM CORRELATE THALAMIC RETICULAR NUCLEUS WITH THE DEVELOPMENT OF THE NEOCORTEX IN Katarzyna Majak Bozena Berdel. Janusz Moqs, MAMMALS? - STEREOLOGIC STUDY Krzysaof Michalewslu Jerzy Dziewiqtkowski. Przemysiaw Kowianski. Jolanta Kowiariska. Janusz Department of Anatom) and h'eurobiologq, Medical Unirerslt) of Morys Gdansk Gdansk. Poland Department of Anatomy and Neurobiology, Medical University of Gdansk, Gdansk. Poland The thalamic reticular nucleus (Rt) is a thin sheet of cells interposed between other thalamic nuclei and the internal capsule. It is composed of GABAergic cells The claustrum is a structure which posses connections with almost all cortical that receive information from both thalamocortical and corticothalamic fibers. The regions. In most of mammals two parts of the claustrum can be easily distinguished: cells in Rt are relatively homogenous Most of them possess long dendrites which larger - the insular claustrum and smaller - the prepirifom. The former send ramify up to the boundaries of Rt. GABAergic neurons of Rt hwerpolarize cells in projection to neocortical areas. whereas the latter - to allocortical. In Primates, other thalamic nuclei inhib~tingtheir activity including Man, the subdivision of the claustrum into two parts is not so clear. The Parvalbumin belongs to calclum binding proteins. It is present in many aim of ow study was to find whether the size of the clausmun corresponds to the neuronal populations of the bran especially in GABA-ergic neurons, and plays a development of the cortex prominent role in calcium dependent mechanism at all stages of development. The The investigations were performed on 27 brains of various mature mammals main aim of our study was to describe the pattern of pawalbumn reactivity in the (Insectivora - Sorex sp ; Rodentia - Rat, Mouse, Guinea pig; Lagomorpha - Rabbit; reticular nucleus during maturation. Carnivora - cat, Primates - Cercupithecus sp , Macaca sp, Man). The brains after The study was performed on 30 rats on various postnatal days. The following removal from the skull were fixed In 8% solution of buffered fomalin, and then stages were examined. PO. PI. P2. P4. PS. P7. P10. P14, P17. P21, P30 and P90. The processed according to standard hstological procedure to obtain the set of paraffin animals were anaesthetized and cut coronally on cryostat Sections were incubated section? stained %ith cresyl violet. The set of morphometric data concerning the for three days with a mouse monoclonal antibody against parvalbumin (Sigma volume of the brain hemisphere, cortex (iso- and allocortex) and claustm were 1:1000). Tissue-bound antibodies were detected using the avidin-biotin peroxidase collected We subdivided animals under study into lissencephal~c(Insectivora, method as indicated by the manufacturer (Vector Labs, Bulingame, CA). Rodentia and Lagomorpha) and gyrencephalic (Primates and Cat). Immunohistochemical control, In which the primaty antibody was omitted d~dnot In all ammals the total volume of the claustrum correlates positively with the show immunostaining. volume of the brain and cerebral cortex. In lissencephalic mammals the increase of In the central part of Rt which appeared at the earliest, the parvalbumin the volume of each part of the claustrum (insular and prepirifom) and the increase immunoposltlve cells were present for the first time at P1. Later, at PI0 neurons of of volume of each main type of the cortex (allo- and isocortex) is similar and the central part showed quite well developed axons aid at P21 numerous correlates with the increase of brain volume. In gyencephalic mammals the increase parvalbumin-positive axon terminals appeared. In the medial and lateral parts the of the total claustral volume is significantly higher than that of the allocortex and cells and axonal temunals became slightly immunopositive at P10 aid at P21 lower than that of Isocortex. respectively. At P30 all parts of Rt were well developed, similarly to those in mature We may conclude that claustrum enlarges with the development of the animals (P90). neocortex, but in smaller degree than the latter, that may have an impact on Our observations show that maturation of pawalbumin-positive structures in Rt functions of the claustm. proceed during the first month of postnatal l~fe

LACK OF INFLUENCE OF THE NEONATAL SEROTONERGIC PERIPHERAL NERVE GRAFTS IMPLANTATION INTO THE OPTIC LESION ON THE FORMATION OF BARREL FIELD OF NERVE AND THEIR INFLUENCE ON THE REGROWTH OF FIBRES SOMATOSENSORY CORTEX IN THE HAMSTER AND RAT AND SURVIVAL OF RETINAL GANGLION CELLS. Nitkowski P., Turlejski K., Djavadian R. Gotka B.,Lewin-Kowalik J., Larysz-Brysz M., Gdrka D., Swiech-Sabuda E., Department of Neurophysiology, Nencki Institute of Experimental Krause M. Department of Physiology, Silesian Medical School, ul. Medykdw 18, 40-762 Biology. 3 Pasteur st., 02-093 Warsaw, Poland. Katowice, Poland In rats, after neonatal depletion of serotonin, cross-sectional area of bundles of thalamocortical axons conducting sensory input from The inability of axons to grow across damaged central nervous system (CNS) single vibrissae to the somatosensory cortex was shrunk by about tissue is a well-known consequence of injury to the brain and spinal cord of adult 20% (Bennet-Clarke et al, 1994). In this study we attempted to mammals. Our previous studies revealed that predegenerated peripheral nerve investigate maps of barrels after serotonergic lesion using the method grafts facilitate neurite outgrowth from the injured hippocampus and that this effect is particuralry dlstinct when 7-, 28- and 35-days predegenerated nerve of staining for cytochrome oxidase, compared rats with hamsters, that grafts were used. The purpose of the present paper was to induce and support the are born at an earlier stage of development. 5,7-dihydroxytryptamine regrowh of injured nerve fibres as well as the sum\~alof retinal ganglion cells. (5,7-DHT) was injected subcutaneously in newborn animals. Experiments were camed out on adult male Sprague-Dowley rats. Animals were Desipramine was injected one hour earlier to protect noradrenergic assigned into three equal groups. In the first and second group, fragment of optic neurons. After 14-30 days of survival, control and experimental nerve was excissed and subsequently a fragment of peripheral nerve was sutured animals were perfused with 4% paraformaldehyde. Cerebral cortex into the site of excission. In the first group, the implanted nerve was freshly taken was cut tangentially to the barrel field on vibratome and the 50 pm but in the second one it had been predegenerated for 7 days. In the third, control sections were stained with cytochrome oxidase. Area of each patch, group, optic nerve was totally transected, sparing the ophtalmic artery, and both ends of cut nerve were sutured one to another. Six weeks folowing surgery representing a barrel was measured with the Imaging Research MCID fluorescent dyes were applied: FITC-DiI into the end of implants and rhodamine image processing system. We found that neither in rats, nor in B to the corpus vltreum. After 48 hrs animals were perfused transcardially and the hamsters there were any differences between the cross-sectional area nerves and retinas were subjected to histological procedures. Labelled cells and of patches between the normal and serotonin depleted animals. For growlng fibres were examined using fluorescence microscope and photographed. example, the area of the cytochrome oxidase patches corresponding They were counted and the results were subjected to statistical analysis. with the barrels C2 was 0.103 + 0.024 rnrn2 in control rats and On the basis of obtained results we can state that the predegeneration of grafts 0.108 f 0.015 mm' in the 5,7-DHT injected animals. Similar results enhance their neurotrophic ~nfluenceupon the injured retinal ganglion cells. In histological specimens it could be clearly observed profuse ingrowth of nerve of measurements of the patches C2 (0.066 f0.0028 in control and fibres steming from the retina Into the grafts. The number of su~vingretinal 0.07 k0.0083 in the 5,7-DHT injected) were obtained in hamsters. ganglion cells was higher in the group treated with predegenerated grafts. Therefore, developmental depletion of serotonin does not seem to permanently influence the morphology of thalamocortical connections. Supported by the Polish Government grant KBN 4P05A 081.11 50 Tuesday, Poster session: Development

Malgorzata Bruska, Witold Wozniak, Piotr Kromer Witold Wo~iak.Malgorzata Bruska

Differentiation of the common afferent tract in early human The development of the subthalamus in human embryos dunng 6th ueek embryos Department of Anatomy. University School of Medical Sciences, Po&

Department of Anatomy, University School of Medical Sciences, Study was made on I1 embryos of stages 15, 16, and 17 Poznan (36 to 41 days). All embnos belong to the Collection of the Department of Anatom! in Pom~and they are catalougued according to developmental The common afferent tract is formed by afferent fibers of stagmg s?stem. Embryos were serially sectioned in different planes the ganglia of the cranial nerves that enter the brain stem and (horizontal. frontal. and sagittal) . In 6 embnos every second or thlrd reach the developing sensory nuclei. This tract contains section was impregnated with silver. descending fibers of the 5, 7, 9, 10 cranial nerves, and with The first indication of the hypothalamus is observed in embryos of stage 15 m which the hypothalamic sulcus appears. The hypothalamus at advancement of the development is divided into sohtary tract, this stage consist of subthalamus and h?pothalamus proper. The trigem~nospinaland vestibulospinal tracts. subthalamus and the the h!pothalamus proper are declineated by shallow Present study was performed in 9 serially sectioned human sulcus which is parallel to the h?pothalamuc sulcus. Betwwn the embryos of developmental stages 13, 14, and 15 (5th week) oculomotor nucleus and the mamillan area are crossing fibers which form belonging to the Collection of the Department of Anatomy in the supramamillan commissure. These fibers are in close relation to the Poznan. In some of embryos graphic reconstructions were made. group of cells in the subthalamic area. This group ma? be considered as The common afferent tract appears first in embryos at primordium of the subthalamic nucleus. stage 13 (31 days) . All sensory ganglia of the cranial nerves are In embnos at stage 16 the subthalamus is represented by large already delineated, but they are not hlly differentiated. The area rich in penetrating capillaries ~vhichare particularly evident in the wide intermediate layer of the subthalamus. On the periphery of of this common afferent tract forms a thick band of fibers on the ventral layer pass hypothalamic fbers. The wide intendate subthalamic zone is part of the hture brain stem . It begins from the entrance of the the source of subthalamic nuclei which may be distinguished during stage afferent fibers of the trigeminal nerve and extends through the 17 in which the ventricular layer of the subthalamic region is much thmner whole length of the cephalic neural tube, beyond the cervical than that of the h>pothalamus. flexure. At the end of the fifth week (embryos of stages 14 and 15) the common afferent tract is joined by fibers from the vestibular nuclel. These fibers are passing on the more ventral surface of the brain, most superficially, close to the surface of the brain stem

DOES SENILE IMPAIRMENT OF CHOLINERGIC SYSTEM IN Movement and posture interaction: age-related RATS CONCERNS DISTURBANCES IN ChAT EXPRESSION OR decline THE ACUTE DEGENERATION OF NEURONAL CELL BODIES? Magdalena Chechiacz 2nd Grazyna N~ewladomsKa Janusz W. Bkaszczyk' and Janusza Kubiczkowa2 The Nencki institate, ?astenr str.3, Warsaw 'Nencki Institute of Experimental Biology, Warsaw, Poland and 2Military Institute of Trophic effect of nerve growth factor (NGF) on basal forebrain (BF) cholinergic Aviation Medicine, Warsaw, Poland neurons, a neuronal population affected during normal and pathological aging, was tested in young (4-mo-old) and aged (28-mo-old) Wistar rats. NGF was injected Decline of integrity in many physiological lntraventriculary via osmotic minipump in the total dose of 80 pg. After one-month, systems in the elderly has a profound effect on continuous NGF delivery the morphometric parameters of BF cholinergic neurons postural stability control. Many systems were analyzed in medial septum, diagonal band of Broca, and magnocellular basal function at less than optimal level; thus, the nucleus. Immunohistochemical procedure for ChAT and NGFp75 receptor has been postural stability control system relies on applied to identifi BF neurons as cholinergic. There was a reduction by as much as degraded information. One of the most commonly 60 - 90% in the number of intensely ChAT-IR profiles in all BF structures of aged used experimental strategy employs the non-treated rats when compared with the young ones. CUT-IR cells appeared vacuolated and shrunken, and the neuropil staining was markedly reduced. In measurement of an input-output characteristics conhast, these same neurons stained for NGFp75r-IR were distinctly visible with of the human body during upright stance. These perfect morphology, regardless of the age of the animals. The cell bodies were characteristics has been studied using sine- densely immunoreactive, with tapering, vericose dendrites forming an intensely wave input produced by subjects themselves. The stained neuropil. Trearment with NGF resulted in a restoration of cholinergic input signal consisted of the torques produced function in the BF neurons of aged rats. NGF increased a number of CMT-IR cells by the manipulandum movement and the output was and caused a significant hy~emophyof these cells in 28-mo-old rats when compared a compound ground reactive forces as recorded with the control, age-matched group. NGF did not influence the morphology of by the force platform. Fifteen elderly (72.02 NGFp75r-IR neurons, which were labeling well, il~espectiveof trearment and age of 8.1 years) and fifteen young (22.7k1.6 years) the rats. adults, participated in this experiment. The The CMT staining suggests that exogenous NGF can reverse age-related results confirmed decline with the age of the impairment in cholinergic phenotype of the BF neurons. The results of NGFp75r maximum speed. The results exhibited also a staining provide some evidence for preservation of these BF cholinergic neurons different perf ormence of the tasks for from ahophy of cell bodies and processes during aging. These data indicate that different loads. The low resistance trials did senile impairment of cholinergic system in rats concerns disturbances in CMT not differe significantly in both groups. Such expression rather than the acute degeneration of neuronal cell bodies per se. differences were, however, seen in the high loads in fast speed conditions. The elderly subjects reduced their postural destabilzation by either decrease of the movement range or by slowing down the movement speed. Tuesday, Poster session: Neuropathology 51

POSTNATAL DEVELOPMENT AND MATURATION OF ADRENAL DIFFERENTLAL EXPRESSION OF hIICROTUBULE-ASSOCIATED MEDULLARY CHROMAFFIN CELLS OF THE GUINEA PIG : A PROTEIN 1B PHOSPHORYLATED ISOFORMS IN THE DEVELOPING HISTOCHEMICAL AND BIOCHEMICAL STUDY. MOUSE BARREL CORTEX. D. Kaczmarczyk and B.L. Kmief Unrhnrn Rfnje~vsknand .lolnntn Skangiel-Krnnrskn, Department of Histology and Embryology, Medical University of t6di, Nencki I~tsfifufeof Experintenfa1 Biology, 3 Pasteur St., Narutowicza 60,90-136 t6d& Poland. 02-093 Warsaw, POLAND

Numerous studies on differentiation of phenotypes of adrenal medulla Microtubule associated proteir~s(MAPS) are a family of proteins which chromaffin cells (CHc) in guinea pigs indicated that epinephrocytes (Ec) show heterogenous spatial and temporal distribution within neurons and i.e. adrenaline(A)-cells were the only cells observed in those sexually ma- are thought to be involved in neuronal plasticih. Among them, MAP-1B is ture animals, and no norepinephrocytes (TVEc) i.e. noradrenali- of special interest for it is elevated during neuror~aldevelopment and neOYA)-cells were detected (Coupland 1965, 1989; Kmief 1976). There down-regulated upon nlaturation. Two modes of phosphonlation have been identified for MAP-1B \\l~ich show distinct de\,elopmental are nevertheless reports showing the presence of low number of NEc in regulatiol~. adrenal medulla of those animals (ErPnkB 1952, 1955; Unsicker et al. To establish developmental changes in the distribution of the two MAP-IB 1978).0n the basis of the mutual developmental line of CHc (Anderson pl~osphoqlated isoforms ill the mouse barrel cortex - a part of the 1993; Unsicker 1993) originating from sympathoadrenal progenitors, somatosenson cortex I\ hich sho~vsstructural and functional plasticity - ne and the fact that in the course of CHc differentiation NEc becomes the performed i~nr~~u~~ol~istocl~e~nicalstudles using monoclonal antibodies 150 intermediate stage in establishing Ec phenotype maturation of those cells and 125 against the modes 1 and 11, respecti] ely. The MAP-IB pl~osphonlation rr~odes 1 and 11 showed distlnct in the PD of the adrenal medulla in guinea pigs was investigated. There developmental pattern of distribution in the rnouse barrel cortex. The 125 were also the attempts to determine with great precision the day of the i~lllnunoreaction first appeared ill supragranular layers and in layer IV as PD in which the final and the only phenotype of adrenal medullary CHc fa~ntstripes of puntcuate fibers on P5, then strenghtened on P12, to in those animals i.e. the phenotype of Ec was established. eve~~tuall!.establlsl~ a mature appearance on P21 when the i~~~rr~unoreactio~~ Adrenal glands ofthe guinea pigs aged 1, 3, 5, 7, 9, 11, 13, 14, 15, 18, 21, became visible also in p) ra~nidalcell perikana. The 125 positive profiles 28, 35 and 90 days (i.e. sexually mature animals) were used in the stu- were identifled as pyrall~idal cell apical dendrites. The 150 immunopositive fibers nere detectable on P5 in infragranular layers Upon dies. Catecholamines (A andlor NA) were revealed employing histoche- nlaturation the 150 ilnmunoreaction dirllinished on P8 and PI0 and was no mica1 methods according to Kmief (1969), Jones (1967) and Hopsu and more detectable on P12. On P21 the immunoreaction re-appeared in layers Mc Kinen (1966). The contents of both NA and A in adrenals were eva- 111111, IV and V. luated by HPLC with electrochemical detection (TVowak et al. 1992). The differential and changing distribution as well as the re-appearance of We showed the presence of NEc in the guinea pigs' adrenals till the age immu~~oreactivityin the adult barrel cortex implies a possible involvemet of approximately 14 day of PD. Gradual maturation of NEc to Ec hap- of the investigated phosphonlated isoforms of MAP-1B in neuro~~al pens this time. This explains the lack of NEc in the adrenals of sexually plasticity induced after the critical period for the barrels formation has ended. mature guinea pigs.

Poster session - Neuropathology

PHAGOCYTOTIC CLEARANCE IN BRAIN APOPTOSIS 'H AND "P MAGNETIC RESONkYCE SPECTROSCOPY D. Maili6ska, M. Muzylak OF THE BRAIN kW SPINAL CORD Institute of Medical Research Centre, Warsaw, Poland DURING ISCHEMIA AND REPERFUSION.

Phagocytotic clearance is the process essential for D. Dobrota', A. Drgovdl, I. TkciP, K MyndriP restoring homeostasis at the site of the tissue injury. T. Liptq3, N Prdnayov&, S. Kafparotvi', M. Pef In the brain, phagocytosis is primarily the function of microglia, cells of which have to be transformed from I Department of Biochmstry, Jessenius Faculty of Medicine, Martin, Slovakia resting to the active ameboid form. The transformation ' MR Centre, Derer Hospital, Bratislava, Slovakia is stimulated by some biologically active compounds 'Central Laboratories, NMR lab, Slovak Technical Umversity, Bratislava, Slovalua excreted by necrotic sells. In apoptosis, such '~e~artmentof Biology, Jessenius Faculty of Medicine, Mart~nSlovakia compounds are not produced and microglia is not activa- ted. The aim of the study is to answer the question Different methods are used to study pathological changes of the central nervous system which cells of the brain parenchyma participate in under nomial and pathological conditions Nuclear magnetic resonance is a physical technique phagocytotic clearance of apoptotic bodies. Study was that has been used as an analytical method, to desmibe the structure of molecules in a specific performed on rabbits. Brain apoptosis was induced by solution. When the sample is placed in a strong static magnetic field the atoms that have intraperitoneal injection of 0.25 mg vincristine sulfate magnetic properties (e.g. lH, 31P, 13C, 19F, etc.) interact with a pulsed radio frequency field. per kg of body weight. Samples of the brains were If the frequency of this field is in resonance with the frequency preclalon of the spins in the embedded in epon and examined in electron microscope. static magnetic field, it is possible to obtain ~nformation regard~ngthe atom's fra,ment As soon as two hours after vincristine injection, chemical structure, from the intensity, phase and frequency of the interaction. Magnetic resonance imaging (MRI) with high resolution images offers the possibility to study some apoptotic cells and numerous apoptotic bodies were morphological changes following ischemic brain injur)., whlle magnetic resonance found in the tissue. Initially, apoptotic bodies were spectroscopy (MRS) allows study of certain biochemical changes, and metabolic pathways in scattered throughout the brain, but four and six hours v~troand in v~vo.The great advantage of MRS is that we are allowed study of these after vincristine administration, most of them were biochemical events in real time without any disturbance of the tissue. engulfed and subsequently digested by the adjacent Investigation of brain and spinal cord changes, with ischermc - repetfusion Injury using 'H and cells. These cells included oligodendroglia, astroglia, "P MRS applicat~onsboth ln vlvo and in vitro was the study's focus. The spectrometers SlSCO 2001330 (4.7 T) and Varian \XR 300 MHz (7.5 T) were used for measurements. The microglia and pericytes. Seven days after treatment In vrbo study of brain tissue perchloric acid extracts, using the Varian \XR 300 MHz apoptotic bodies were sporadically found in cytoplasm spectrometer, showed that w~ththe 'H spectrum it is possible to detect a few metabolites with of some those cells. Our results show that following low molecular weight. The most expressive signals were produced by creatine, inositol, brain apoptosis various type parenchymal cells are aspartate, choline, N-acetylaspartate, glutamate, glutamine and lactate. During the ln vivo engaged in immediate removing of apoptotic bodies and study of ischemic brain tissue it was possible, using the spectrometer SISCO 200, to obtain a suggest that these cells employ different than in spectrum from the volume of interest at 150 p1. The spectral lines were broader than in the ln vlrro spectra; s~gnalsfrom the lactate, N-acetylaspartate, creatine, phosphocreatine and choline necrosis, mechanism of recognition and ingestion of were detected as well. The mast important fmdings were observed in the time - dependent tissue debris. increased lactate level, and in the small decreases of N-acetylaspartate. "P in vivo measurement shows an mntensive signal from the a, P, y ATP phosphate group, phosphocreatine (PCr), inorganic phosphate (Pi), phosphodiesters and phosphomonomters. It was possible to detect that the signals from ATP and PCr d~sappearedfrom the spectn~mand the Pi signal became very intense after 40 minutes of ischemia It seems that MRS IS a very promising method of ischemic - reperfusion mjur). investigat~on. 52 Tuesday, Poster session: Neuropathology

TRANSIENT SPINAL CORD ISCHEHIA AND NADPH-d ISCHEMIA-INDUCED ALTERATIONS OF ACTIVITY ENDOPLASMIC RETICULUM CALCIUM STORES FROM J, HAR~ALA,D. KLUCHOVA, H. MAR~ALA.INSTITUTE THE GERBIL FOREBRAIN. OF_ NEUROBIOLOGY, SLOVAK ACADEMY OF SCIENCES, KOSICE, SLOVAK REPUBLIC J. Lrhotskj, P. Raday, P. Kaplail. I.: Mire.fova, C'omeilius [Jilil:, Silver impregnation analysis of neuronal Jesseililrs Medical Faculty, Martill, Slovakia damage and concurrent histochemical It is widely accepted that disturbances of calcium homeostasis characterization of NADPH-d positive neuronal play a key role in the development of cell damage following by pools in the rabbit lumbosacral segments was performed during and after transient spinal cerebral ischemia Endoplasmic reticulum is believed to play an cord ischemia. Strongly enhanced staining of important role in the neural cell ca2' handling during normal and NADPH diaphorase positive neurons and their pathological conditions. Forebrain ischemia (5 to 15 min) was processes appeared in the superficial dorsal induced by ligation of both common carotids and reperfusion by horn (laminae 1-111). pericentral region (lamina X) of lower lumbar segments, lateral subsequent release of ligature ca2- pump mediated ca2- collateral pathway, and mainly in neyrons of accumulation was shown to be depressed by15 min ischemia to the sacral parasympathetic nucleus in Sa 37.3% of control values. The ca2- uptake activity partially segment at the end of 40 min of abdominal recovered after 1 hour reperfusion, however it still remained aorta ligation or one day after reperfusion. Despite development of extensive neuronal depressed to 68.1% of controls. No significant changes were degeneration in the central gray matter detected in the kinetic parameters of c~'--ATP~s~after ischemia. (laminae IV-VII) between 1-4 days after As detected by quantitative Western blotting, transient ischemias ischemia, a number of non-necrotiaing neurons had no effect on the level of endoplasmic ca2--transport proteins. localiaed in the areas corresponding with the 10 min, ischemia and prolonged reperfusion, however selectively distribution of NADPH diaphorase positive neurons was detected suggesting a selective down-regulated levels of InsP3 receptor and plasma membrane resistance of these pools of neurons against ~a'--~um~,with the most profound alterations after 72 h to 10 transient ischemic insult. It is postulated days No significant changes have been detected in levels of that region-specific synthesis of nitric oxide SERCA 2b protein and of calreticulin These findings indicate that and its vasodilatatory effect during the period of incomplete spinal isahemia may ischemic-reperfusion insult alters membrane properties of ca2'- account for the observed selectice resistance stores which eventually could lead to their depletion Since the of these spinal cord neurons to transient filling state of endoplasmic reticulum is in a close relation to many ischemia. cellular processes, including protein synthesis and gene expression, Supported by Grant 2/1104/94 from the Slovak Academy of Sciences. we suggest that disturbances in reticular calcium homeostasis may contribute to ischemic cell injury.

ML LTlFLlNCTlONAL ROLE OF CALPAIN IN BRAIN ISCHEMIA EFFECT OF 7-NITROINDAZOLE ON NITRIC OXIDE MEDIATED Teresa Zalewska, Barbara Zabiocka, Kqstyna Domanska-Jan~k BIOCHEMICAL AND MORPHOLOGICAL ALTERATIONS EVOKED BY Lab Mol Neuropathol , Dept Neurochem , Medical Research BRAIN ISCHEMIA MAtGORZATA CHALIMONIUK* AND JOANNA STROSZNAJDER Centre, Pol Acad Sc~ences,Paw~nskiego 5, 02-106 Warsaw, Poland Department of Cellular Signalling Medlcal Research Centre Pollsh Academy of Sclences 5 Pawiiisklego Street PL-02106 Warsaw Poland Calpa~n(ca2+-act~cated cystelne protease) is one of the med~atorsof In thls study the actlon of 7-nitrolndazole (7-Nl) on nltrlc oxlde synthase (NOS) actlvlty and cGMP level durlng dlfferent time of reperfuslon abnormal ca2+ s~gnalIn lschemic braln It has two well characterized untll 7 days after 5 mln of lschemla In gerbll braln hemlspheres and ~soforms,p- and m-calpain, d~stingu~shableon the bas~sof dlfferent cerebellum was Investigated Moreover we trled to ldentlfy the role of NO In calcium requirement m-calpain is acticated at mlcromolar, m-calpa~n membrane l~poperox~dat~onsactivated durlng reperfusion Anlmals were at m~ll~molarfree ~a2+concentration Intracellular local~zationand treated wlth lnhlbitor whlch appears to have some selectlvlty to nNOS 7-NI 5 mln before lschemla in a dose of 25 mglkg b w It was observed that proteolyt~cactlvlty of two calpain lsozymes as well as breakdown translent forebrain lschemla enhances significantly ~a~+/calmodul~n products of the calpain specific substrates were incestlgated In global dependent NOS actlvlty and cGMP level In braln hemlspheres and also In cerebral lschem~aIn rats and gerb~ls The SDS-PAGE and Western cerebellum non lschemlc part of braln Durlng reperfuslon blphaslc Increase blot analys~s of calpa~ns together with determlnatlon of the of NOS actlvlty and cGMP level took place w~thtwo peaks 15 mln and 2h after proteolyt~c breakdown products were performed in soluble and lschemla The cGMP level that enhanced durlng reperfuslon IS NO - dependent The amount of conjugated double bounds (CDB) In membrane membrane fractions obtalned after centrlfugat~on of braln llplds and the level of thlobarblturlc acld reactlve substances (TBARS) homogenate as well as In post-svnaptic densit~es(PSD) It seems that Increase significantly durlng reperfuslon In braln hemlspheres lndlcated the Ischemia Induces two dlfferent but Interrelated effects on calcium- activatlon of 11p1dperoxidatlon 7-Nltrolndazole (7-Nl) eltmlnates enhancement dependent proteolyt~csystem of NOS activity and cGMP level In braln hemispheres and cerebellum evoked by lschemla Moreover the NOS lnhlbltor decreases slgnlficantly the early 1 The rapld actleation, as was detected In the present study bv phase of membrane llpld peroxldatlon but ~thas no slgniflcant effect on the Increased cleavage of calpaln substrates spectrln and proteln klnase level of CDB and TBARS 2 hours after ischemic Insult These results C, extensice calpaln assoclatlon with the particulate fract~on, suggest that NO IS Involved In activatlon of membrane ilpld peroxldatlon durlng the early tlme of reperfuslon after lschemlc Insult Histolog~cal enhanced autoproteolvs~sof m-calpain proenzyme to its actlee, post- examlnatlon demonstrated that 7-NI protects agalnst death a very small autolyt~cspecles population of neuronal cell In CA, layer of hlppocampus analysed 7 days after 2 Gradual, t~me-dependentdown-regulat~on of the total m-calpa~n lschemla It IS suggested that NO release durlng reperfuslon through actlcltv wlth a concomitant increase of calpastatin actlclty actlvatlon of free radlcals formation and subsequently through stlrnulatlon of The abllitv of tlssue to keep these two actleatory and inh~bitory membrane lhpld perox~datlonmay be lnvolved In alteratlon of blochemlcal processes in braln leadlng to the degeneration of some population of processes In balance m~ghtdetermine the final outcome from the neurones Moreover lschemla evoked NO dependent slgnal transmlsslon to ischem~cep~sode cerebellum may have blochemlcal and functional consequences Our results Supported by the Med~calResearch Centre and partially by lndlcated that 7-NI In splte of amelloratlng effect on lschemla evoked the KBN grant k 4P05A 026 08 biochem~calalteratlon IS not able to prevent death of neurons

'M Chalimonluk IS a recipitent of Foundation for Pollsh Science grant Tuesday, Poster session: Neuropathology 53

THE PROTECTIVE EFFECT OF CARNOSINE DCRINC EXPERIMENTAL BRAIN ISCHEhlIA IN RATS

S. Stvolimky', .Zf. Kukukley', D. Dobrotd, E Buly ind, G. KrmarenPo3, A. Boldyro.', K ,l.fP:efowif

I Institute of Seurology, Russian Academy of Medical Sciences, Moscow, Russ~a I Department of Biochemistry, Jessenlus Faculty of Medicine, Marti& Slovakia Department of B~ochemsiry,Jessemus Faculty of Medicine, Mart,& Slovakia 21ilstitute of Neurology, Russ~anAcademy of Medical Sciences, Moscow, Russia Department of Biochem~stry,School of Biology, Moscow State University, Moscow, Russia ' MR Centre, Derer Hospital, Bratislava, Slovakia

Oxygen deficiency and tlssue reoxygenation effects a discharge of free radicals Many functionally important neuron proteins are membrane-bound and formatlo& llpld peroxldatlon and direct oxidation damage to prote~nsand nucleic aclds. At onset depend on the nat~vityof the lipid environment; during Bee radical attack they of ischemic injury, reactive oxygen species are formed in the hydrophilic cell space, and the suffer both from the direct chemical modification and Bom membrane structure protective role of hydrophilic antioxidants seems to be important. In the current research we ha\< d~sorderingby the peroxidation process. In the current research we have studled the studled the effect of camoslne, a natural hydroph~l~cneuropeptide possessing antioxidant wlth activity of NaK-ATPase (p-mtrophe~lphosphatase) and monoaminooxidase, lipid membrane-protective properties, during expaimental brain ischemia in rats. NMR-spectroscopy peroxldation levels and membrane fluidity, dung different brain ischemia penods allowed us to show the significant lactate elevatio~accompanied by a demeased N-acetyl-aspartate m rats signal after 15-45 mm. in brain ischemia (4-vessel occlusion). In rats treated with camosine before Complete bram Ischemia (4-vessel occlusion). P-mtrophe~lphosphatase ~schem~a,lactate accumulat~onwas much lower and the changes in the N-acetyl-aspartate signal werenot significant We have compared cell membrane conditions and the activity of some activity m the rat's brain was significantly decreased (62-85% of control level) after membrane-bound enzymes aRer brain ischemia in rats, both treatedluntreated with camosine kfore 15 and 45 rmn of ischemia, as well as after ischemia followed by 30 min. and 24 the surgery. ARer 15 minutes of brain ischemia, the rat's brain lipid peroxidation level was about hrs, reperfusion The monoaminooxidase activlty in brain cells rmthochondria was 86% of the control animals, and (Al'S) arul~nonaphtalinosulphonate'sfluorescence maximum was decreased up to 85 and 60 % of the control level after 15 and 45 min. of ischemia, about 86-95s of the control in different membrane f?actlons. In rats treated with camosme (150 and reperfus~on led to the. eweactivlty restoration. Accut~lulation of l~pid mgkg body weight daily administered with the drinking water) for 10 days kfore surgery, the peroxldation products in the braln after different periods of complete ischemia was measured parameters were similar to that of the control group, to wit: lipid peroxidation level at about 86-95% The decrease of (ANS) anilinonaphtalinosulphonate fluorescence 98% of the control, fluorescence maxunum of ANS about 100%. Fifteen minutes of ischemia while in rats maxlmum after 15 min. of ischem~awas not veq slgruficant (92-95% of control); followed by 24 hrs of reperfuslon displayed ANS maxunum fluorescence at 76% treated with camos~ne ths ~arameter was about 98.100%. The demease of p- but subsequent reperfus~onand longer ischemla penods (45 min ) led to a further n~u.jph

NFKB p65 SUBUNIT IN THE RAT BRAIN: UNUSUAL AXOPLASMIC EFFECT OF fl-AMYLOID PEPTIDES ON CHOLINERGIC RECEPTOR- PRESENCE AND LACK OF EARLY NUCLEAR TRANSLOCATION MEDIATED CALCIUM SIGNALING IN BRAIN CORTEX FOLLOWING NEOCORTICAL INFARCTION. SYNAPTONEUROSOMES D. TORZEWSKA, M. ZAREMBA AND M. SKUP, Samochockl M.. Chalimoniuk M, and Strosznajder J. NENCKI INSTITUTE OF EXPERIMENTAL BIOLOGY, WARSAW. Department of Cellular Signalling, Medical Research Centre, Polish Academ~Sc~ences, 5 Paulnskiego St., 02-106 Warsaw Poland Devascularizing infarction of the neocortex leads primarily to death of cortical and In this stud!, the effect of two fragments of O-amyloid peptides (AD) 1-28 thalamic neurons;followed by a gradual atrophy and loss of cortical tissue within and 25-35, on the resting and muscarlnic cholinerglc receptor (mAChR)-~nduced the infarct. The changes are accompanied by induction of nerve growth factor increase of c!tosol~c calcium concentration ([Ca],) In adult braln cortex (NGF) and NGF TrkA receptor expression within a subpopulation of cortical and s)naptoneurosomes was investigated Result nas compared \nth the effect of aging of thalamic reactive astrocytes and by a decrease of NGF and TrkA expression in mAChR-evoked lnosltol trisphosphate (IP3)-mediated Increase of [Ca],. The release of injured nucleus basalis magnocellularis neurons. In search for the mechanisms of IP3 \\as measured after l~p~dprelabell~ng \!ah myo-[3~]inositolChanges in [Ca], postinjury neuronal degenerationand regulationof NGF expression we investigated \\ere monitored b! uslng fura-2 lndlcator The effect of AD pept~deswas evaluated by in M'VO the presence and activation state of the p65 subunit of the inducible theu prelncubat~on \v~thproteln 1. 5, 30 and 60 mln, before startlng of [Ca], measurement It \!as observed that in aged brain. ~a"-dependent and mAChR- transcription factor NFKB shown to mediate in vitro neuroprotective actions and mediated IP3 production \\as not changed In comparison 1~1ththe adult braln over 60 NGF activation in astrocytes. The immunocytochemical study was carried out on mln of incubat~onActlvatlon of mAChR in adult brain for 10 min Increased [Ca], by adult, Wistar, male rats, 0.511, 1.5h, 311 and 611 following unilateral cortical about 50.60% over its resting level, nh~ch\\as completel) blocked b) muscarinic infarction. Naive and sham-operated animals served as controls. NFKB p65 antagonists, atropine and pirenzeplne, as well as b! antagonist of [PI receptor, TMB- antibody (1: 1000, Santa-Cruz) and ABC Vectastain kit were used. In control rats 8 In aged brain. there were no detectable changes In [Ca],, due to mAChR weak constitutive perikaryonal NFKB labeling found in most of the brain neurons stlmulation AD 25-35 peptide caused a t~me-dependentsignificant increase In [Ca], remained in contrast with heavy perikaryonal and axonal staining found within nhich \\as almost five-fold after 60 min of Incubation The action of AB 1-28 on reticular thalamic neurons, dorsomedial, lateral, periventricular and perifornical resting [Ca], \!as stat~st~call!lns~gnificant up to 30 mln, then a rap~dincrease of hypothalamic area. Dense, heavily labeled fiber networks within mfb, substantia resting [Ca], b? tuo-fold \\as observed up to 60 min of incubation Both AR pept~des innominata, internal capsule, claustrum and sepmm were found. Lesion did not decreased markedh mAChR-evoked elevat~onof [Ca], In adult braln After 60 mln of affect NFKB labeling pattern and intensity within subcortical areas but caused prelncubat~on1~1th 1-28 AR. the activation of mAChR enhanced rest~ng[Ca], by about spatially restricted enhancement of perikaryonal labeling in the devascularized 30%, \\hereas 25-35 AB eliminated thls receptor-dependent calcium mobilizat~on cortical fields. Neither p65 nuclear translocation nor nonneuronal p65 expression These results lnd~catedthat the neurotoulcit? of deposited B-amylo~dma! take a part was found. The study documents for the first time axoplasmic localization of in decreasing of mAChR-eioked IP3-med~atedcalcium mobllizat~onand may further NFKB p65 subunit and extends data on p50 subunit presence within synaptosomes lead to alteration of muscarlnlc receptor-mediated slgnal transduct~on in brain (Kaltschmidt et al., Mech. Dev. 43, 1993). Results support the view of NFKB function as a retrograde messenger mediating stimulus-response coupling following presynaptic stimulation and suggest no early (hours) NFKB involvement in postinjury neuronal and glial responses. Supported by the KBN grant to Nenckl Institute and KBN grant #I030 to M Skup 54 Tuesday, Poster session: Neuropathology

N\IDA .AND GLUTAkIIC ACID INDUCED CHANGES IN Recovery from Acoustic Trauma: An Ultrastructural and EXPRESSION OF p-APP AND TAU PROTEIN IN PAIRED Immunohistochemical Study on Regenration of Hair Cells in HELICAL FILAMENTS (PHF) "IN VIVO" the Chick Basilar Papilla Wanda Gordon-Krajcer and Mohd Alaraj Department of Neurochem~stry, Med~calResearch Centre, Pol~sh M. ~liwinska-~owalska,A. Rzgdzinska, U. Jedlinska, Academy of Sciences, Pawlnsk~ego5, 02-106 Qarsaw, Poland E. Rajkowska Accumulation of p-amyloid prote~n (P-A), P-amyloid precursor proteln (p-APP) and appearance of bundles of palred L)ej)c7rnnenr of' Phqrlcnl Hnzordr.. helical filaments (PHF), the neurofibrillarq tangles, has been found in N(tfc.rhsrrrnre of' Occ~~porronfllMedrcine. Alzhelmer d~seaseThe alm of th~sstudy was to establish changes in 90-950 todz. P 0. Box 199. Poiond the expression of some of domains of P-APP and tau proteln in PHF in rat hlppocampus after stereotactic mlcroinjection of 1 PI of 2 or Acoustic overstunulation produces a loss in the audrtory eprthel~um 5 mM NbDA and 1 mM or 2 mM glutamic acid to To detect In postembnon~cmammals, the loss of audrtory ha~rcells is thought to be more precisely the role of NbIDA receptors In modulat~onof p-APP permanent and to result m irreversible hearing deficiency. In birds, however, degenerated audrtory ep~theliummay be replaced by new ha~rcells, which processing and PHF immunoreactiwty, MK-801 or CPP which are probably originate from the support cells ofthe basilar papllla antagonists of ?IMDA receptors were injected lntraperltoneally 30 The aim ofthe study wsto assess by light and transmission electron min before experiments Separation of proteins form hippocampal nilcroscopy the cytological and fme structural changes of the newly tlssue by electrophores~swas followed by their Western blot analysis dexloping ha~rcells and neural elements during post-traumatic regeneration using antibodies against some domains of P-APP and tau In PHF It in the chick. We have also studied, by ~mmunochistochemical method, was found In th~sstudy that appl~cationof glutamic acid or NMDA to prollferat~on cell nuclear antigen (PCNA) in relatlon to the regeneratlon the rat hlppocampus Induces s~gn~ficantchanges In the pattern of P- process. APP fragments and tau In PHF Th~spattern changes durlng tlme of The study was performed on 1-day-old Whlte Leghom chicks, recovery (2h, 12h, 24 h, 72 h) after lnject~onand are more ewdent exposed to broad-band nolse at high intensity for 5 consecutive days, 4 hours after Nh4D.4 then glutam~cac~d appl~cat~on .After 24 hrs and 72 hrs a day. The structural changes of the basilar papilla and PCNA expression the enhanced lmmunoreactlvlty of all P-APP domams, particularly of were assessed on days 1,4 and 6 after exposure. PA (whlch was dose-dependent, sensltlve to MK-801) and of the C- We confirmed that the proliferation of sensory cells m the chlck termmal fragment of P-APP was noted After 72 hrs enhanced bas~larpap~lla starts from the first days after nolse exposure The schedule of Immunoreactl\lt\ of all tau epltopes In PHF was observed Our regeneratim of hatr cells and neural elements IS descnbed m detail m thls study The presence of PCNA 1s a good marker of cell drvision and correlates results will be d~scussed In relatlon to PHF changes obser\ed In well with the regeneratlon process of halr cells in the chick basllar papilla Uzhe~merd~sease Supported bq the KBN grant #4 P05.4 059 08

MODULATORY EFFECT OF BOVINE SPINAL CORD HYDROLIZATE UPON THE EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS IN THE RAT. IMMUNOCYTO- CHEMICAL STUDY Barbara Kwiatkowska-Patzer, Maria Barcikowska, Bozena. Baranowska* and Andrzej W. Lipkowski Medical Research Centre, Polish Academy of Sciences, Pawiriskiego 5, 02-106 Warsaw and *Industrial Chemistry Research Institute, Rydgiera 8, 01-793 Warsaw. Specific protein feeding is known method of induction of tolerance of immunologic response to this antigen. This method is reviewed recently by some authors as a possible tool in the treatment of autoagressive d~seases. Experimental allergic encephalomyel~t~s (EAE) is the respected an~malmodel of such autoagressive disease as multiple sclerosis. The alm of the study was evaluation of the effect of bovine splnal cord hydrolizate given orally upon the course of EAE in the rat. Experimental allergic encephalomyelitis was evoked in Wistar rats by intradermal injection of homogenate of spinal cord of guinea pig w~thFreund's adjuvant and Myocobacterium phle~. Since the end of first relapse rats were fed of bovine spinal cord hydrolizate three times a week and also evaluated clinically in bllnd fash~on Clln~calcourse of EAE In treated anlmals group was mllder In comparlson to the control ones 4t SIX weeks post lmmunlsatlon ~mmunocytochem~calstudy showed Increased ratlo of CD41CD8, decreased ~mmunolog~calanswer to CD68 and decreased reactlon w~th aTNF ant~bod~esIn the group of treated an~mals w~th hydrol~sateIn comparlson to the control In conclus~onthese p~lotdata ~nd~catethat oral treatment w~thsplnal cord h) drollsate modulate cl~n~calcourse, ~mmunolog~cresponse and patholog~cImage of EAE In the rat and m~ghtalso have some cl~n~cal ~mpl~cat~on Tuesday, Poster session: Excitztory amino acids 55

Poster session - Excitatory amino acids

DEVELOPMENTAL CHANGES IN PHIKAINATE BINDING SITES IN THE NEONATAL BLOCKADE OF NhOA RECEPTORS THE BARREL CORTEX OF MICE ALTERS THE DOPAMMRGIC NECXOTRANSMISSION AND SENSORIMOTOR GATING IN RATS B. Jablofiska, M. Kossut, J. Skangiel-Kramska K. F6laiLM. Maiko~r,rak,A. ('zyak atld K. PVqdzoiy. The Nencki Institute, 02-093 Warsaw, 3 Pasteur st. Irisflt~rreqf Pharmncolog~,Po11sh Academy of Scrc~nces,31-3-13 Krakriu, I2 Snqftza street, Polarid L-Glutamate is the major excitatory transmitter in connections to and Recently it has been suggested that glutamate driven from the cortex and between cortical areas. Glutamate mediates excitatory activity in the neurons through its activation of three types of ionotropic impairments of neurodevelopment may lead to hyperactivity of receptors (NMDA, AMPA, kainate) and metabotropic receptors. The dopaminergic neurotransmission and in consequence to the present work is focused on developmental changes of distribution of psychoses in adult life. Therefore, the present study investigated the kainate receptors present in the specific area of somatosensory cortex - the effects of neonatal administration of a competitive NMDA receptor barrel cortex. The barrel cortex is a locus of representation of sensory antagonist CGP 401 16 on functional parameters characteristic of the whiskers of the snout of mice. To examine the pattern of distribution of dopanlinergic neurotransmission, i e sensitivity of rats to r3H]kainate binding sites the quantitative receptor binding autoradiography amphetamine and quinpirole, and on the density of dopamine D-1 was used. We found that kainate binding sites were present in the cortex and D-2 receptors, as measured by an autoradiography (using of newborn mice (PO). During the initial three days of life PHlkainate ['HISCH 23390 and ['~ls~i~eroneas ligands. respectively) We binding rapidly increased. Then, from postnatal day 8 (P8), binding rose found that chronic neonatal administration of CGP 401 16 enhanced slowly, and the adult levei (500 fmollmg protein) was reached at P12. Later the labeling remained quite stable until P28. No barrel-like pattern exploratory activity of rats and augmented the locomotor stimulant of ['Hlkainate binding sites could be discerned in tangential sections effects of amphetamine and quinpirole. Such a functional obtained from cortex of adult mice. Clear developmental interlaminar supersensitivity was accompanied, at receptor level; by an increase in changes of [3H]kainate binding in the barrel cortex were registered. At P3 the number of D-1 receptors in substantia nigra. It was also found in immature layer IV the highest binding of PHIkainate was observed. By that neonatal administration of hWAreceptor antagonist abolished P5, a high labeling is also present in layer V. At P12, when the adult the prepulse-induced inhibition of acoustic startle response, this panern of receptor binding distribution is established, the densest labeling effect being antagonized by clozapine It is concluded, for the first, is concentrated in layers VIVI, moderate in layer IV and the lowest in that blockade of NMDA receptors during development may lead to supragranular layers. Thus, in contrast to AMPA receptors, kainate the overactivity of dopaminergic systems, and secondly, that it binding is concentrated in infraglanular layer from the second postnatal induces impairments in experimental animals which resemble some week. deficits seen in patients suffering from schizophrenia

AGED RELATED CHANGES OF NMDA RECEPTOR MEDIATED NITRIC EFFECTS OF THE PENTYLENETETRAZOLE-LNDUCED OXIDE DEPENTED SIGNALING PATHWAY IN BRAIN. EFFECT OF KMDLING ON THE NMDA RECEPTOR GENE AMYLOID P PEPTIDES. EXPRESSION IK THE RAT HIPPOCAMPUS Chalimoniuk M. and Strosznajder J. Department of Cellular Signalling. Medical Research Centre, Polish Jadwiga Turchan, Domlnika tabuz, Barbara Przewlocka, Ryszard Academy Sciences, 5 Paninslaego St, 02-106 Warsaw Poland Przewloclu, Wtadyslaw Lason Department of Molecular Neuropharmacology. Institute of In central nervous s)stem, activation of glutamlnerg~creceptor NMDA t)pe Pharmacology, Pol~shAcademy of Sc~ences,Krakow. Poland nas shoun to Induce ca2+- dependent NO s!nthesis, ah~chactivates soluble guanklate clclase and leads to the formailon of cGMP Both compounds appear to be Important mediators In long term potentlation ILTP), mechanism respons~ble for A number of data lndcate an lnlponant role of NMDA receptors In seuure processes of learning and memon Aglng IS an Important rlsk factor for lmpainnent of phenomena Agorusts of \MDA rcceptors eloke h\pmncluonous dscharges memon and dementla In these studles the mechan~smof basal and NMDA receptor and Induce beha\loral scvures nhereas the~rantagomsts suppress the xvure mediated. cGMP formation In different part of adult and aged braln was anallzed actnm and present de\elopnient of e\penmental epileptogenesis It has ken The studies were camed out uslng hlppocampal, bra~ncortex and cerebellum slices li>pthes~sedthat changes In the NMDA receptor b~oslnthes~sma\ be ~rnol\ed from 4 months and 27 months old animals The relative function of the NO cascade In the ~necharusniof kindling - an atun~almodel of epilepn nheretn pendc was detemed b) measurement of NO s!nthase and guan!late cyclase using subthreshold electrical or chem~calst~n~ulat~on leads to long-last~ngneuronal rad~o~mmunochernicalmethods In these assays specific agonlst and antagonist of h~pere\c~tab~lmIn order to test tlus h\pthesis In a tlme course studs ne NMDA receptor and selective enz!me mhibltors were used In addition, the effect of insest~gatedthe effects of penhlenetetra~olek~ndl~ilg on the eyresslon of a gene different s)nthet~cAP pept~desAP25-35 and APl-lO on the NOlcGMP messenger NMDA system nas evaluated. It was found that brain agmg is coincident &ith a decrease of a dngfor NMDARI and the denslp of receptors in the rat luppocampal basal level of cGMP as a -consequence of more active degradation of cGMP b) fonnat~on As shonn b! an In situ h\bnduation stlid\ the penplenetetrazole phosphod~esteraseas compared to adult brain Moreover a loss of NMDA receptor lundllng decreased the NMDARl nlRNA lael In the CAI field and dentate response evoking an enhancement of cGMP level deternlined In the presence of g\rus at 7 and 24 h after the last lnjectlon of the con\ulsant A receptor cGMP-phosphodiesterase uhb~tor(Dm) aas found in hippocampus and autoradograph~showed an Increase in the ['HIMK-801 blndng denslh in the cerebellum, but not In braln cortex of aged matched controls A significant stratum oncns stratum radatum and stratum moleculare or the luppocampus of enhancement of NO s)nthase actlrit), by about 175% and 160% m hippocampus and kindled rats Ho\mcr the altcrauons In both the WAR1ntRVA le\el and the cerebellum of aged braln, observed In our stud~es,ma! be responsible for NO- dens~hof ['HIMK-sOI \\ere back to control \dues on dl\ 15 after the last dependent alteration of receptor or enzyme protein It was found that AD 25-35 lnjectlon of penh~enetCt~ZOle The transience of the abxe changes In the aiiected significantly NMDA receptor mediated NO dependent signaline pathway hosnthes~sof luppocampal NMDA receptors suggesls that the%are rather an These alterations ma) hare funct~onalconsequences In disturbances of learning and adaptne response to repeated sevures rather than a cause of pemianent neuronal memo? processes in aeed brain li\pere\c~tab~l~t\. Supparted b\ grant 6 P207 140 06 obtained from the State Conmuttce for M Chalirnoniuk is a recipient of Foundation for Polish Science grant. Sc~ent~ficResearch (KBN) 56 Tuesday, Poster session: Excitatory amino acids

MODULATION OF NMDA-EVOKED PROSTAGLANDIN D2 CHARACTERIZATION OF METABOTROPIC RECEPTORS FOR RELEASE IN RABBIT HIPPOCAMPUS IN VIVO EXCITATORY AMINO ACIDS WHICH STIMULATE CYCLIC AMP J.W. Lazarewicz, E. Salihska, A Stafiej, A. Ziembowicz and ACCUMULATION IN RAT BRAIN E. Zieminska Agnieszka Pahcha, Piotr Branski, Beata Legutko, Andrzej Pilc Department of Neurochemistry, Medical Research Centre, Polish Institute of Pharmacology Polish Acad. Sci., 31-343 Krakow, Sm$na 12, Academy of Sciences, Pawilisluego 5, 02-106 Warsaw, Poland Poland Prostaglandin D2 (PGD2), a biologically active product of Glutaminic acid (Glu) is a major excitatory neurotransmitter in the cyclooxygenase, is involved in various brain functions. Our previous central nervous system. It activates several subtypes of ionotropic glutamate studies with in vivo microdialysis demonstrated NMDA-induced, receptors, as well as metabotropic glutamate receptors (mGluR). Stimulation Ca2+ dependent eicosanoid release in the rabbit hippocampus Here of mGluR leads to formation of dierent second messengers in the cell. The we characterise NMDA receptor dependence of PGD2 production in aim of our experiments was to investigate the effect of different agonists of this experimental model, its relation to extra- and intracellular Ca2+ mGluR on cyclic AMP formation in slices from rat brain cerebral cortex. The pools, and to nitric oxide (NO). All drugs were applied with microdia- formation of cyclic AMP was measured using a prelabelling technique with lysis medium, dialysates were analysed for concentrations of PGD2 preincubation of slices with H adenine. We found that the endogenous (with RIA), of amino acids (with HPLC), of NO (with haemoglobin transmitter Glu in doses up to 2500 uM induces a dose dependent statistically trap), and for changes in 45Ca2+ efflux, The results: a dose-response significant increase in cyclic AMP formation with the EC, of 440 bM, after relation between NMDA concentration and PGD2 release and its higher doses a gradual decrease in cyclic AMP formation was observed. inhibition by competitive NMDA receptor antagonists, demonstrate Substances which activates several subtypes of mGluR such as ibotenic acid the role of NMDA receptors. NMDA-evoked PGD2 release was ac- or 1S,3R-1-aminocyclopentane-l,3-dicarboxylicacid (lS,3R-ACPD) also companied by a drop of 45~a2+efflux, indicating a decrease in ex- induced a dose dependent increase in cyclic AMP accumulation with EC,, of tracellular Ca2+ concentration due to its influx to neurones, and by 142 and 70 pM, respectively. Quisqualic acid which stimulates group I of release of taurine and phosphoethanolamine, known to be partially mGluR did not affect cyclic AMP fomlation as well as and agonist of Ill group Ca2+ dependent. These effects were resistant to dantrolene and of mGluR - L-SOP. However compounds which are rather selective towards ryanodine modulation suggestin a marginal role of the ryanodine group II of mGluR such as (L-CCG-I), 3-carboxy-4-hydroxyphenylglycine sensitive pool of intracellular C$+. NMDA application resulted also (3C4HPG) and 4-Carboxy-3-hydroxyphenylglycine(4C3HPG), also induced in NO release to dialysate, which was sensitive to L-NAME. This NO a dose depenendt increase in cyclic AMP formation with the EC, of 142, synthase antagonist had no effect on NMDA-evoked decrease in 227 and 209pM, respectively. This indicates that the stimulation of II subtype extracellular Ca2+ concentration, but inhibited PGD2 release, which of mGluR is responsible for an increased formation of cyclic AMP. This is consistent with a direct cyclooxygenase activation by NO. hypothesis is further supported by the fact that the action of mGluR II Supported by the KBN grant 4P05A.045.08, and by the Foundation agonists was inhibited by (RS-alpha-methylserine-0-phosphate-monophenyl for Polish Science (program BRAIN). ester (MSOPPE), which is an antagonist of the II group of mGluR.

LACK OF THE RELATIONSHIP BETWEEN THE CONCENTRA- LACK OF PROTECTIVE EFFECTS OF MAGNESIUM SULPHATE TION OF MAGNESIUM IN BLOOD PLASMA AND THE DEATH INTRA VENOUS INFUSION ON THE DEATH RATE AFTER NMDA RATE IN RATS AFTER ADMINISTRATION OF N-METHYLO-D- INJECTION INTO THE 3rd CEREBRAL VENTNCLE IN RATS. ASPARTATE (NMDA) INTO THE 3rd CEREBRAL VENTRICLE B.Jakubowska-Naziembto, B,Dziedzic, W.Z.Traczyk K. Aslanowicz-Antkowiak, B. Jakubowska-Naziemblo. B. Dziedzic, Department of Physiology, Institute of Physiology and Biochemistry, W. Z. Traczyk Medical University of Lodz, 90-1 3 1, Poland Department of Physiology, Institute of Physiology and Biochemist~y, Medical University of Lodz, 90-13 1 Lodz. Poland Recent evidence suggests that the neurotoxicity of endogenous exitatory amino-acids plays an important role in the pathogenesis of the Numerous experimental studies performed on animals and also brain damage. The magnesium exerts protective effect by blocking the clinical reports indicate the suppressing action of magnesium salts on calcium influx through ion channels which are coupled to the N-methyl- the cytotoxic effect of excitatoly amino acids. D-aspartate (NMDA) receptors. The aim of the studies was to fmd the relationship between the The present study was undertaken to determine whether a concentration of magnesium in blood plasma and the death rate of magnesium sulphate infusion into the veins of rats before or after the animals after the infusion of NMDA into the 3rd cerebral ventricle. NMDA injection into the 3rd ventricle may have an ~nfluenceon the The experiments were canied out on 30 adult male rats. In a survival of the rats. stereotaxic apparatus. under i.p, barbiturate anaestesia all animals were 80 adult male rats were divided into five experimental groups. infused intracerebroventricularly with 10 pL of a solution containing Anaesthetized rats received a single injection of 10 p1 of 0.9% NaCl 400 nmol of NMDA. Prior to the NMDA infusion blood fiom the tail solution (control group) or 200 nmol (low dose) and 400 nmol (high dose) vein was collected in order to assess the concentration of magnesium of NMDA to the 3rd ventricle. The NMDA was injected 30 minutes ions. before or 30 minutes after the 12.5 % MgS04 infusion into the vein. After the NMDA infusion 8 animals died within 25 - 60 minutes In the control group all rats survived the experiment, which was and 7 rats died after several hours up to 34 days. In the group of animals carried out over 80 days. The low dose of NMDA injected into the 3rd which survived 80 days after the NMDA infusion the average plasma ventricle caused the death of 27 % of rats, while the high dose of NMDA concentration of magnesium ions was 1.90 f 0.05 mEq I L plasma caused the death of 80 % of rats. The animals died after several minutes (within the range of 1.64 - 2.22 mEq I L). In the group of animals which or a few days. This effect was dependent on the dosage of NMDA but not died after the NMDA infusion the average plasma concentration of on the moment of MgSO, infusion into the vein. These data demonstrate magnesium ions was 1.87 + 0.04 mEq I L plasma (within the range of that magnesium sulphate infusion into the vein cannot prevent the 1.62 - 2.40 mEq i L). neurotoxic effect ofNMDA injections into the 3rd ventricle in rats. The significant difference in the concentration of magnesium ions Supported by KBN grant No 4 P05B 164 08 in blood plasma in surviving animals and in those that died after the NMDA infusion was not ascertained. Th~swork was supported by /he KBNgran! Nr 4 POjB 164 08 Tuesday, Poster session: Excitatory amino acids 57

CHANGES IN GONADOTROPIN RELEASING HORMONE (GnRH) INFLUENCE OF INTRASTRIATAL INJECTIONS OF 5,7- CONCENTRATION IN THE DIENCEPHALON AND PITUITARY DICHLOROKYNURENIC ACID, AN ANTAGONIST OF GLYCINE AFTER N-METHYL-D-ASPARTATE INFUSION INTO THE 3-RD SITE OF THE NMDA RECEPTOR, ON THE HALOPERIDOL- CEREBRAL VENTRICLE IN MALE RATS. INDUCED MUSCLE TONE. B. Dziedzic, B. Jakubowska-Naziembto, K. Aslanowicz- Antkowiak, Lorenc-KOCI E., Wolfarth S., Ossowska K. Institute of Pharmacology, W.Z. Traczyk Polish Academy of Sciences, 12 Smetna St., 3 1-343 Krak6w (POLAND); Department of Physiology , Institute of Physiology and Biochemistry, Medical University of Lodz, Lodz, 90- 13 1 Lodz, Poland The consequence of a dopamine deficit in the striatum of parkinsonian patients seems to be a shift of the equilibrium between dopamine and There is evidence that N-methyl-D-aspartate (NMDA) by glutamate towards the glutamaterglc system. Animal studies Indicate that stimulation of the hypothalamic gonadotropin releasing hormone (GnRH) competitive and non-competitive antagonists of NMDA receptors are able to is involved in the control of LH secretion. restore the dopamlnergic-glutamatergic balance and thus induce an We investigeted the effect of intraventricular administration of antlparklnsonian effect. Ho~vever,these drugs produce a lot of side-effects. NMDA on GnRH concentration in the diencephalon and pituitary in adult Antagonists of the modulatory glycine site of the NMDA receptor seem to male rats. The hexobarbital anasthetized animals were placed in a be devoid of such effects. stereotaxic apparatus and through a cannula inserted into the 3rd cerebral The alm of the present study was to find out whether 5,7-DCKA, ventricle infused with NMDA in three doses: 100, 200 and 400 nmol. The an antagonist of the glycine site of the NMDA receptor, counteracted the dose of 400 nmol proved to be lethal in 50 % of animals. After 80 days all haloperidol-enhanced muscle tone in the rat, a model of parkinsonian animals, which survived were decapitated. The brains were removed and rigidity. The experiments were carried out on male Wistar rats which were diencephalon and pituitary were isolated. In tissue extracts the GnRH injected bilaterally wlth 5,7-DCKA in doses of 1, 2.5, 4.5 pg in a volume of concentration was determined by radioimmunoassay. 0.5 p1 in the rostral part of the striatum. The muscle tone was measured as Intraventricular administration of NMDA in the dose of 200 and mechanical resistance of the hind foot, developed in response to passive 400 nmol significantly (p = 0.001) increased GnRH concentaration in the movements in the ankle joint. The EMG acticity of the gastrocnemius and pituitary in comparison with intact animals. The increase after 100 nmol tibialis anterior muscles was simultaneously recorded. 5,7-DCKA, injected of NMDA was not statistically significant. Infusion of three doses of intrastriatally, caused a significant and dose-dependent decrease in the NMDA resulted in an insignificant increase in GnRH concentration in the haloperidol-induced muscle tone. Similarly, a tendency to decrease the diencephalon as compared with the control, intact animals. EMG activity in the musculus tibialis anterior during extension and in the The present study indicates that intraventricular administration of musculus gastrocnemius during flexion was observed NMDA increased GnRH concentration in the pituitary and diencephalon The present results indicate that blokade of the glycine site of the probably by affecting the process of GnRH synthesis and release. NMDA receptor complex in the rostral part of the striatum may be important to the antyparkiIIS0nian effect of drugs. Supported by KBN grant No 4 POSB 164 08.

ANTIPARKINSONIAN ACTION OF L-701,324, AN ANTAGONIST CGP 40116, A COMPETITIVE ANTAGONIST OF NMDA OF THE GLYCINE SITE OF THE NMDA RECEPTOR COMPLEX, RECEPTORS, AND THE PROTECTIVE POTENCY OF COMMON ON THE HALOPERIDOL-INDUCED MUSCLE RIGIDITY IN RATS. ANTIEPILEPTIC DRUGS AGAINST MAXIMAL Koniecmv J*, Schulze G,Ossowska K*, Wolfarth S*. ELECTROSHOCK Czuczwar S.J., Hussein Q., Kleinrok Z. Department of Clinical Neurobiology, Free University of Berlin, Berlin, Department of Pharmacology and Toxicology, Medical University GERMANY; Department of Neuropsychopharmacology, Institute of School, Jaczewskiego 8, 20-090 Lublin, Poland Pharmacology, Polish Academy of Sciences, Krakow, POLAND Antagonists of NMDA-induced excitation, apart from their anticonvulsive effects per se (Czuczwar and Meldrum, Eur. J. Pharmacol., 83,335,1982), L-701,324, an antagonist of the glycine site of the NMDA receptor may augment the anticonvulsive activity of conventional antiepileptic drugs complex has been shoun in a number of tests to have a pharmacological against maximal electroshock (Czuczwar et al., Eur. J. Pharmacol., profile of an atlpical neuroleptic, devoid of extrapyramidal effects in rats. 100,357,1984; Czechowska et al., Eur. J. Pharmacol., 232,59,1993). The aim of the present study was to find out whether this compound However, some combinations exerted serious adverse effects (Zarnowski affected the haloperidol-induced muscle rigidity of the parkinsonian type, et al., J. Neural. Transm., 97,1,1994; Neuropharmacology 33,619,1994). which \\as recorded mechano- and electromyographically in rats CGP 40116 (an active isomer of CGP 37849) was consequently combined (MMGEMG). with antiepileptic drugs. An influence of CGP 401 16 upon the free plasma The MMGEMG method measures the muscle resistance of the levels of antiepileptic drugs as well as their adverse effects was also rat's hind leg, evoked by passive flexions and extensions in the ankle joint, evaluated. At a subprotective dose of 0.5 mglkg (90 min before the test) as well as the simultaneous electromyographic activity (EMG) observed in against electroconvulsions, CGP 40116 reduced the ED,, value of flexor (tibialis anterlor) and extensor (gastrocnemius) muscles of the hind carbamazepine against maximal electroshock from 12 to 5.3 mglkg, that of leg during movements. Our previous experiment shoved that haloperidol diphenylhydantoin - from 12.3 to 4.7 mglkg, that of phenobarbital - from (0.5-10 mgkg) induced dose-dependent muscle rigidity of the parkinsonian 16.5 to 8 mglkg, and that of valproate - from 254 to 145 mglkg. At 0.125 tlpe This drug simultaneously - especially at higher doses - increased mglkg, CGP 40116 was still able to potentiate the protective potency of muscle resistance and late components of the reflex EMG activity to these antiepileptics. In no case the NMDA receptor antagonist affected the movements. free plasma levels of antiepileptic drugs as measured by imrnunofluore- L-701,324 in doses of 2.5-10 mgkg decreased the muscle rigidity scence. Only its combinations with valproate were associated with impaired induced by 1 mgkg of haloperidol; used in doses of 10-40 mgkg, it motor coordination and long-term memory. Considering these results, one diminished the muscle rigidity evoked by 5 mgkg of haloperidol. However, may postulate a clinical significance for these combinations, especially in L-701,324 given alone in doses equal to or higher than 5 mgkg induced epileptic patients with increased plasma levels of excitatory amino acids. ataxia related to muscle ngidlty. The present results indicate that glycine antagonists used in doses devoid of motor side-effects may be usefbl in the treatment of parkinsonian rigidity. 58 Tuesday, Poster session: Excitatory amino acids

INFLUENCE OF LY 300164 (A NOVEL NON-NMDA ANTAGONIST) ON RILUZOLE, AN INHIBITOR OF GLUTAMATE RELEASE, THE ANTICONVULSIVE ACTIVITY OF ANTIEPLLEPTICS POTENTIATES THE PROTECTIVE ACTIVITY OF Czuczwar S.J., ~wiaderM., Kuiniar H., Kleinrok 2. CONVENTIONAL ANTIEPILEPTIC DRUGS AGAINST Department of Pharmacology and Toxicology, Medical University ELECTROCONWLSIONS IN MICE School, Jaczewskiego 8, 20-090 Lublin, Poland Czuczwar S.J., Drelewska E., Kleinrok Z. Excitatory amino acid antagonists affecting NMDA or non-NMDA receptors have Department of Pharmacology and Toxicology, Medical University been shown to enhance the protective effects of conventional antiepileptic drugs. School, Jaczewskiego 8, 20-090 Lublin, Poland Some combinations resulted, however, in profound adverse effects (for review see Czuczwar et al., Metab. Brain Dis., 11,143,1996). It was therefore of interest to Agents blocking iohotropic receptors for excitatory amino acids have been examine the influence of a novel non-NMDA antagonist, LY 3001647 [7-acetyl-5- documented to augment the anticonvulsive action of antiepileptic drugs (4-aminophenyl)-8,9-dihydro-8-methyl-7H-l,3dioxolo(4,5-H)-2,3-knzcdiazepine], against maximal electroshock-induced seizures in mice (Borowicz et al., on the protective effects of antiepileptic drugs against electroconvulsions. LY Eur. J. Pharmacol., 281,319,1995; Epilepsia 37,618,1996). A question 300164, up to 2 mgikg, did not influence the threshold for electroconvulsive arises whether such an activity may be shared by the glutamate release seizures. In doses of 2.5 - 4 mgikg, LY 300164 significantly raised the threshold. inhibitor, riluzole. Riluzole alone (1.25 and 5 mglkg, 30 min prior to the In subprotective doses against electroconvulsions, this excitatory amino acid test) significantly raised the threshold for electroconvulsions (tonic antagonist enhanced the protective activity of valproate, carbamazepine and di- extension of the hind limbs taken as the endpoint) from 6.2 to 7.8 and 9.2 phenylhydantoin against maximal electroshock-induced convulsions in mlce. The m.4. In lower doses, the inhibitor of glutamate release did not affect the anticonvulsive action of phenobarbital was potentiated by LY 300164 only at 2 threshold. When combined with antiepileptic drugs, riluzole at 0.625 mglkg mgikg. The non-NMDA receptor antagonist dld not affect the plasma levels the potentiated the protective potency of carbamazepine, diphenylhydantoin, antiepileptic drugs, so a pharmacokinetic interaction is not probable. The comblned and phenobarbital. The potentiating action of riluzole was the most evident treatment of LY 300164 (2 mg/kg) wlth the antiepileptics studied (providing a 50% protection against maximal electroshock) did not impair the motor performance of in the case of carbamazepine and diphenylhydantoin whose ED,,s against mice, evaluated in the chimney test. Valproate, at its ED,, of 280 mglkg against maximal electroshock-induced seizures were reduced from 14.4 to 8.7 maximal electroshock, produced motor ~mpairment.As shown in the passive mglkg and from 10 to 5.7 mglkg, respectively. The combined treatment of avoidance task, combination of LY 300164 (2 mglkg) with valproate or riluzole with antiepileptic drugs did not affect the motor coordination of diphenylhydantoin resulted in impairment of long-term memory. Among mice evaluated in the chimney test. As regards long-term memory antiepileptic drugs alone, valproate (280 mglkg) and phenobarbital (28.5 mglkg) (evaluated in the passive avoidance task), only a combination of riluzole disturbed long-term memory. The results suggest that the blockade of glutamate- with diphenylhydantoin impaired this parameter. It may be suggested that mediated events via non-NMDA receptors leads to the enhancement of the similarly to the blockade of glutamate-mediated events, an Inhibition of its anticonvulsive activity of conventional antiepileptic drugs. Some combinations of release in the central nervous system may lead to the enhancement of the LY 300164 with antiepileptic drugs were superior than these antiepileptics alone antiepileptic drug-induced protection against maximal electroshock, a in terms of adverse effects. widely recognized model of generalized tonic-clonic seizures in humans

7-NITROINDAZOLE (A SELECTIVE NEURONAL NITRIC OXIDE NMDA ANTAGONISTS COUNTERACT CHRONIC STRESS- SYNTHASE INHIBITOR) DIFFERENTIALLY AFFECTS THE INDUCED DEFICIT OF AGGRESSION ANTICONVCZSIVE ACTIVITY OF CONVENTIONAL G. Ossowska, B. Klenk-Majewska, G. Szymczyk ANTIEPILEPTICS IN MICE Department of Clinical Pharmacology, Medical University School, Czuczwar S.J.,Borowicz K.K., Kleinrok Z. Department of Pharmacology and Toxicology, Medical University Jaczewskiego 8, 20-090 Lublin, Poland School, Jaczewskiego 8, 20-090 Lublin, Poland Nitric oxide (NO; a small membrane-diffusible molecule) is probably involved It has recently been suggested that the NMDA subtype of in the modu1a:ion of seizure activity. Both, pro- and anticonvulsive actions of glutamate receptors may be involved in the mechanism of action of NO have been documented. Consequently, it was of interest to study the effect antidepressant drugs. Our previous studies have shown, that the rats, of 7-nitroindazole on the protective activity of conventional antieplleptic drugs subjected to chronic stress procedure, exhibited a decreased against maximal electroshock-induced seizures. At 25 and 50 mglkg 7- footshock-induced fighting behavior and that prolonged treatment nitroindazole, 30 min before the test, did not influence the electroconvuls~ve with antidepressants counteracted this effect of chronic stress. threshold. However, at 50 mglkg, it enhanced the anticonvulsive activity of present study, investigated the effect of two non- phenobarbital against maximal electroshock (the ED,, value of phenobarbital In the we was decreased from 17.7 to 7.3 mglkg) and did not affect that of competitive NMDA antagonists: dizocilpine (MK-801) or memantine, carbamazepine, diphenylhydantoin, and valproate. L-Arginine (500 mglkg) did given in the single dose or for 14 days, on footshock-induced not modify the protective activity of phenobarbital alone or the 7-nitroindazole- fighting behavior and exploratory activity in normal or chronically induced enhancement of its anticonvulsive potency agalnst maximal stressed rats. electroshock. 7-Nitroindazole did not alter the plasma levels of antlepileptic It was found that repeated application of various kinds of drugs, so a pharmacokinetic interaction, in terms of total and free plasma stressors decreased the footshock-induced fighting behavior and that levels, is not probable. 7-Nitroindazole combined with the antiepileptics prolonged treatment with memantine (2.5 mgikglday) or MK-801 resulted in motor disturbances, except of the combination with phenobarbital. (0.1 mgikglday) restored the intensity of fighting behavior to control On the other hand, the combined treatment of 7-nitroindazole with carbamazepine or phenobarbital produced effects superior to those produced level. A similar effect was observed in stressed rats receiving the by single drugs, as regards long-term memory. Our results indicate that the single dose of MK-801 (but not of memantine), but this effect was protective activity of carbamazepine, diphenylhydantoin, or valproate against accompanied by locomotor stimulation. maximal electroshock may be not dependent upon the central NO level. The The results of the present study indicate that non-competitive enhancement of the anticonvuls~veaction of phenobarbital by 7-nitroindazole NMDA antagonists can reduce the behavioral deficit produced by is probably not related to the decrease of NO in the central nervous system. chronic stress. This effect is similar to that of antidepressant drugs. Tuesday, Poster session: Excitatory amino acids 59

Role of NMDA receptors in ultrasonic vocalizations in The effect of ACPC on rewarding properties of some drugs of abuse. 50 kHz band during acquisition of sexual behavior in P. Gruca, J. Wieronska, M. Papp, Institute of Pharmacology, Polish male rats Academy of Sciences, Krakow, Poland. M. Rvdz, M. Bialy, L. Kaczmarek The majority of psychoactive substances that are abused by people have Nencki Institute of Experimental Biology, Warsaw, Poland rewarding properties, and therefore, the understanding of neurochemical Acqusition of copulatory reaction by male rats exposed to mechanisms underlying these effects is one of the major purpose in receptive females provides an interesting model of learning modern studies on psychobiological processes involved in the processes. We have previously shown that shortening of mount development of drug dependency and its therapy. A growing number of and intromission latencies occurs rapidly, within 1-2 traning sessions (each session up one ejaculation only) during such preclinical data suggest that some aspects of drug abuse and dependence training. To the contrary, decrease in ejaculation latency as well as may be attenuated by the NMDA receptor antagonists. However, there are increase in ultrasonic vocalizations in 50 Hzband (U-bc) emitted also reports suggesting that these agents have strong reinforcing and by males during 5 rnin of habituation to copulatory cage, before introduction of female are requiring at least three training session psychotomimetic properties. Therefore, in recent years intensive studies to be significant. To test a role of NMDA receptors in these have been carried out to identify compounds which would inhibit function phenomena, we trained the naive males up to 10 copulatory of the NMDA receptors indirectly, e.g. acting at strychnine-insensitive sessions (single ejaculation in each session). One group of animals 25 minutes before each session received injection of glycine sites coupled to the NMDA receptor complex. There reasons to Ringer's solution (RS). The second received injection of 0.1 believe that these compounds share many of the pharmacological actions mglkg MK-801 at the same regime. The third was treated to of both uncompetitive and competitive NMDA antagonists without their injection of RS before the first five training sessions, and unwanted side-effects. The present paper reviews results of studies afterwards - the males received MK-801. In the fourth group, the order of treatment was reverse. We suggest that the increase in designed to evaluate the effect of ACPC, a high affinity, partial agonist at number of U-bc corresponds with learning process and NMDA strychnine-insensitive glycine sites, on the acquisition and expression of receptors play an important role in this phenomena. a place preference conditioning induced by morphine, cocaine, amphetamine and diazepam. These results will be discussed in terms of the involvement of the NMDA receptors in brain mechanisms of rewarding activity of those drugs of abuse and the possible use of various ligands of the NMDA receptor complex in the therapy of drug dependence in humans.

The increasing of susceptibility for kyotorphin in picrotoxin-induced kindling Shandra A.A., Godlevsky L.S., Brusentsov A.I., Vastyanov R.S. State Medical University, Odessa, Ukraine

Kyotorphin was shown to suppress seizures in cases of acute epileptic activity in rats and mice. We performed the investigations aimed to study the kyotorphin effectivity in picrotoxin (PTX) kindled rats. bdling procedure was performed by dady i.p. PTX injections in subthreshold (1.3 mg\kg) dose. Peptide was injected i.c.v. in dose of 10 nmoles % hr before the testing PCT injection after the kindhng termination (24-th PTX injection). Kyotorphin showed simcant antiepileptic efficacy in kindled animals which was expressed both in seizlu-e latency prolongation (on 44%, P<0.01) and seizure severity decreasing (P<0.05). This antiepileptic effect was blocked by preliminary naloxone (0.1 mgkg). Hense, the data obtained revealed the expressed antiepileptic profile of kyotorphin effects. It should be stressed the singificance of kindled seizures inhibition - the very complicated form of seizures and considered to be a drug- resistant form of seizures. Named effect is realized via p- opioid neurotransmitter system. 60 Tuesday, Poster session: Peptides

Poster session - Peptides

OPPOSITE DOPAMINERGIC REGULATION OF EFFECTS OF NEUROPEPTIDE Y ON EPILEPTIFORM ACTIVITY NEUROPEPTIDE Y AND CORTICOTROPIN RELEASING IN THE CORTEX M VITRO. FACTOR IN THE RAT AMYGDALA Marla B~jak Inst~tuteof Pharmacology, Polish Academy of Sciences, Smetna 12, M. ~mialowska,M. Bajkowska, B. Przewlocka* 3 1-343 Krakow, Poland Department of Neurobiology and *Department of Molecular The 36 amino acid peptide, neuropeptlde Y (NPY) is the most Pharmacology, Institute of Pharmacology, Polish Academy of abundant peptlde in the mammalian brain. High concentratlons of Sciences,12 Smetna St., 31-343 Krakow, Poland NPY are found in the cortex. Several studies have shown marked increases In cortical content of NPY after experimentally induced Prevlous studles lndlcated that dopamlnerglc (DA) lnnervatlon seizures, which leads to a hypothesis that NPY may serve as an may affect the expresslon of certaln neuropeptldes In some braln endogenous anticonvulsive agent. In fact it has been reported that structures In the present study we performed a selectlve NPY lnhlblts some forms of epileptiform actlvity In the unilateral 6-OHDA leslon of mesencephal~c DA neurons hippocampus and cortex in vitro. The aim of this study was to projecting to the amygdala The effect of denervatlon was determine the effect of NPY on epileptiform activity In the rat observed uslng ~mmunoh~stochemlcalmethods In two different frontal cortex in vitro. neuronal populat~onsIn the amygdala neuropept~deY (NPY) Perfuslon of a cortical slice with saline containing nominally zero and comcotropln releasing factor (CRF) neurons The NPY or Mg2-, results in the appearance of synchronous discharges. NPY CRF lmmunoreactlve (-lr) neurons In the amygdala were counted potently and reversibly inhibited the frequency of the discharges In mlcroscoplc sections, and comparisons between lesloned and This effect was mimicked by the Y1 receptor agonist (~eu~', contralateral sldes, and versus sham-operated controls were NPY but not the Y2 receptor agonist NPY13.36. One posslble made explanation for the inhibition of epileptiform activity is that NPY A slgnlficant Increase In the number of NPY-lr neurons was has effects on electrical properties of cortical neurons or on found In the amygdala on the lesloned slde In companson wlth glutamate release. Neither the resting membrane potential, input the contralateral one (170%) and sham-operated rats The resistance, discharge properties nor the excitatory postsynaptic number and stalnlng lntenslty of CRF-lr neurons decreased In the potentials evoked by electrical stimulation were affected by NPY ~psllateral amygdala (40% of contra) The obtalned results apphcation The possible target of NPY action still remains to be lndlcate an opposlte DA regulation of the NPY and CRF elucidated. The presented data support the hypothesis that NPY may play the role of an endogenous antiepileptic agent in the cortex. expresslon In neurons of the rat amygdala Supported by the KBN grant No. 4P05A05211 Tlus st114 aas supported b, the KBN grant No 4 P05A 101 09

THYROLIBERIN (TRH) AFFECTS THE OXYTOCIN AND PROLACTIN THE EFFECT OF MELATONIN ON OXYTOCIN RELEASE UNDER RELEASE IN FEMALE RATS DURING MIDLACTATION STRESS CONDITIONS Joanna Ciosek, Jan W. Guzek, Boiena Stempniak and Ryszard Dqbrowski Marlena Juszczak, Boiena Stempniak, Ewa Bojanowska, Jan W. Department of Pathophysiology. Medical University of Lodz, Poland Guzek, Ryszard Dqbrowski. Department of Pathophysiology, Medical University of todz, Poland. TRH is possibly engaged in functional regulation of the hypothalamo- neurohypophys~alsystem. This experiment was performed to study the effects of TRH on oxytocln (OT) and prolactin (PRL) release in lactating female rats Melatonin (MEL) modifies the release of oxytocin (OT) as brought not suckled or suckled. Primiparous female Wlstar rats in midlactation, isolated about by some pathological conditions such as dehydration or from their litters 12-14 hrs before the experiment, were used The animals were hemorrhage. The aim of the present investigations was therefore to divided into two groups: A - rats injected intracerebroventricularly (i c.v.) with study the effect of MEL on OT release under immobilization stress. 10 pl of 0.15 M NaCI, B - rats treated with TRH administered i.c.v. at a dose of Male Wistar rats were divided into two groups: A) animals 200 ng dissolved in 10 pl of 0.15 M NaCl solution. In each group two subgroups injected once daily for two weeks with melatonin vehicle (1% ethanol in were set up- I - females not suckled: II - females suckled during 30 minutes. On 0.9% NaCI; 0.1 ml per 100 g. b.w.), B) animals similarly injected with the day of experiment, a permanent cannula was implanted into the lefl cerebral melatonin solution (50 pg1100 g, b.w.). In each group three further ventricle of urethane-anaesthetized an~malsAt the end of surgery the rats were 1 - given intravenously (I.v.) propranolol (250 pglkg b w ) to facilitate the milk subgroups were chosen: rats euhydrated, i.e.,they had free access ejection reflex One hour later a blood sample (time ,,Om')was collected. to food and tap water during whole experiment; 2 - animals dehydrated Immediately thereafter the animals were injected 1.c.v. with respective solution (i.e., they did not have access to food and tap water) for 24 hours and the pups were allowed to suck the appropriate females for 30 minutes before decapitation; 3 - animals dehydrated as animals of group 2 and (subgroups A-ll and B-ll) In all animals, the blood samples were also collected additionally immobilized (i.e.,singly transferred into small cages where 5. 10, 15 and 30 minutes (time ,,5,.,lo", .,I5 and ,.30) after 1.c.v. infusions. they could not move freely) for 24 hours. The animals were Plasma OT concentration in TRH-treated lactating but not suckled decapitated between 9.00 - 9.30 a.m. and the OT content in the females (subgroup B-I) increased distinctly 5. 10 and 15 minutes after injection neurohypophysis (NH) as.well as plasma levels of OT and ACTH were in comparison with not suckled females treated with vehicle; at time ,.30" it radioimmunoassayed. returned to the control level. In females suckled and treated with normal saline h in NH. (subgroup A-ll) OT plasma level increased at 5th and 10th minute of suckling Dehydration for 24 did not modify the OT content the A s~ngle1.c.v. dose of TRH inhibited the OT release in response to suckling. However, immobilization decreased the content of OT in NH both in Plasma PRL concentration in not suckled females remained unchanged from vehicle- and MT-treated rats. Neither dehydration nor immobilization time ,.O' up to the end of experiment. 1.c.v. injection of TRH distinctly raised PRL modified the plasma OT levels in vehicle-treated rats. However, after plasma level in not suckled females The PRL plasma level of suckled females MT treatment plasma OT level was diminished in euhydrated animals ralsed at 15-th minute of suckling. Contrary to TRH effect in not lactating but slightly increased in immobilized rats. Melatonin injections animals, TRH caused significant decrease of PRL level in blood plasma of significantly inhibited the rise in plasma ACTH levels as brought about lactating females suckled by their litters over 30 mlnutes. by immobilization. It 1s concluded that the effects of TRH on OT and PRL release in On the base of the present results we conclude that MEL seems lactating females are different In not suckled and suckled animals to increase OT release but inhibit ACTH release under conditions of immobilization stress. Tuesday, Poster session: Peptides 61

LHRH - A hEUROMODIJL4TOR OF THE HYPOTHALAMO- INFLUENCE OF THE SYMPATHETIC EFFERENTS ON NEUROHYPOPHYSIAL SYSTEM ACTIVITY NEUROHYPOPHYSIAL HORMONS RELEASE IN RAT Eha Bojanokbska, Bozena Stempn~ak.Marlena Juszczak. Jan W Guzek, Rqszard Dqbrou sk~ Lipinska S., Traczyk W.Z Department of Pathophqslologq. Med~calUnlvers~ty, Lodz Department of Physiology, Institute of Physiology and The secretory activity of the hqpothalamo-neurohypophysial system Biochemistry, Medical University of I,odz, Lindleya 3, 90-13 1 (HNS) is affected by a number of factors of neural as well as hormonal Lodz, Poland. origin. We have found recently that intracerebroventricularly injected The aim of the present study was to investigate whether the luteinizing hormone releasing hormone (LHRH) alters the vasopressin stimulation of the superior cervical ganglion (SCG) or superior release in the rat The present stud? was designed to investigate in vitro cervical ganglionectomy (SCGx) have the influence on the some mechanisms possibly involved in the LHRH - HNS interactions. The hypothalamo-neurohqpophysial complex (the intact pituitary stalk vasopressin and oxytocin release from the posterior pituitary lobe has preserved) obtained from male Wistar rats was incubated in 1 ml The experiments were performed out on male rats under general of the Krebs-Ringer buffer (KRB) gassed with carbogen at 37°C. The anaesthesia. The animals were divided into five groups: 1) control, medium was changed every 20 min. After a 60-min. equilibration period. 2) 20 days after SCGx. 3) immediate after SCGx, 4) after the the HNS was ~ncubatedsuccessively in: (1) the normal Krebs-Ringer preganglionic fibers of the SCG stimulation, 5) after blooding (1 % fluid (BI). (2) the hypertonic KRB with excess of sodium (osmolality = b.w.).The venous blood from the sella turcica region dialysis was 320 mOsm/kg H20)or in the KRB containing 30 mM potassium (SI), carried on. Vasopressin and oxytocin content was determined in the (3) normal medium alone or with 40 nM LHRH (B2), (4) the incubation dialysates by radioimmunoassay. In chronic animals 20 days after fluid as (2) in the presence or absence of LHRH (S2). Vasopressin concentrations in the samples were radioimmunoassayed and the ratios bilateral SCGx the oxytocin and vasopressin content in dialysates B2/B1 and S2/S1 calculated and compared using Wilcoxon test. were 4 times higher per time unit then in control animals. Superior LHRH sign~ficantly(p < 0.01) inhibited basal vasopressin secretion, ceniical ganglionectomy immediate before dialysis evoked several the ratio B2/B1 decreasing from 1.7 f 0.3 to 0.9 f 0.2. Similarly, LHRH times increase in vasopressin and oxytocin release like after reduced both hyperosmoticallq challenged vasopressin secretion blooding. SCG stimulation increase four times vasopressin and (the S2ISI ratio from 0.85 f 0.12 to 0.47 f 0.07; p < 0.05) and K'- oxytocin release. stimulated hormone release (the S2/S1 ratio from 1.3 f 0.4 to 0.7 f 0.1 On basis of results obtained, it my be presumed that noradrenergic p < 0.01). efferents probably decrease in neurohypophysial hormones release, We conclude that LHRH is involved in the regulation of the HNS but stimulation of the superior cervical ganglia increase its release. function b> the inhib~tor)impact on the vasopressinergic neurons' actiwty. The study was supported by a grantfor Medical University of Lodz.

INFLUENCE OF OSMOTIC STIMULATION ON VASOPRESSIN In\ol~crncntof histalnine in the CRH and vasol~rcssin-induced (AVP) AND CARDIODEPRESSANT FACTOR (CDF) RELEASE l~ituitary-;~drenocorticnl~~csl~onsc. INTO THE BLOOD A. Gorqca, Traczyk WZ Anna Olowska, Anna Gqdck-Micllalska, Janusz Borycz, Radoslaw Glod. Department of Physiology, Institute of Physiology and Jan Bugajski Depart~nentof Pl~ysiology,Institute of Phar~nacology,Polish Academy of Biochemistry, Medical University of Lodz, Lindleya 3, 90-131 Sciences. Krakow, Poland Lodz, Poland The aim of this study was an attempt to reveal if CDF and Vasopressin (AVP) derived from the l~ypothalamicparaventricular AVP were simultaneously released from the pituitary into blood nucleus is a well documented coregulator of ACTH release froill the after osmotic stimulation, and if excitatory amino acids blockers anterior pituitary. The release of both corticotropin-releasinghormone influence AVP and CDF release to osmotic stimulation. The samples (CRH) and vasopressi~ifrom the I~ypotlialamicneurons and ACTH from of dialysates of the blood outflowing from the sella turcica region the pituitary corticotrops is coregulated by neurotransmitters. We found and from the femoral vein were collected in anaesthetized rats. At tllat stirnulatory effect of CRH on the pituitay-adrenocorticalaxis does not the beginning of the collection of the 2nd 30 rnin dialysate samples markedly depend on central histaminergic ~nechanis~ns.The secretion of hypertonic saline andlor 200 pg of selective receptor antagonist D, cortlcosterone induced by systemic or intracerebroventricular adn~nistrationof CRH in rats was not substantially affected by ip or icv L-2-amino-5-phosphonopentanoic acid (AP-5) or non-selective pretreatment \\it11 the histamine HI-and H2-receptor antagonists, receptor antagonist 6,7-dinitroquinoxaline-2,3(lH,4H)-dione mepyramine and cimetidine. Also l~ypotl~ala~nicand hippocampal (DNQX) was infused intraarterially. In dialysate samples AVP histan~inelevels were not ~narkedyaltered by treatment with CRH. concentration was measured by RIA and CDF on spontaneously A possible involvement of brain histamine and its receptors in the AVP- discharged pacemaker tissue of the right auricle of the right heart induced ACTH and corticosterone response is not clear. Vasopressi~igiven atrium of a two-day-old rat. Osmotic stimulation simultaneously ip significantly increased the hippoca~npalhistamine level as well as serum caused increase in AVP and CDF concentration in the blood corlicostero~~ecollcentration. Histamille syntl~esisinl~ibitor dialysate from the sella turcica and from the femoral vein. Blockade a-fluoro~i~etl~yll~istidineco~~siderably decreased the AVP-elicited of excitatory amino acids receptors by AP-5 and by DNQX hippocampal histamine and serum corticosterone levels. Histamine HI- and significantly decreased in the blood dialysate AVP and CDF H2-receptor antago~~ists,mepyramine and cimetidine, also markedly impaired the vasopressin-induced increase in the hippocampal histamine concentration elicited by intraarterial injection of hypertonic saline. and serum corticosterone levels. Pretreatment with the histamine H3- Excitatory amino acids are involved in the mechanism of the release receptor antagonist tl~ioperalnidesignificantly diminisl~edtile AVP-elicited of blood AVP and CDF to osmotic stimulation. corticosterone response, but did not alter the histamine content in eitl~er The study was supported by a grant for the Medical University of Lodz brain structures esamined. These results indicate that histamine H1-, H2- and H3-receptors and hippocampal histamine are involved in mediation of the AVP-induced pituitary-adre~~ocorticalresponse, whereas llistaminergic nlccl~a~~~sn~sare not in\olved in tile response elicited by CRH. 62 Tuesday, Poster session: Peptides

Prostaglandins and nitric oxide regulate adrenocortical response Modulatory effects of galaninergic system in the rat striaturn to vasopressin in stressed rats Shandra A.A., Godlevsky L.S., Vastyanov R.S. State Medical University, Odessa, Ukraine Anna Gadek-Michalska, Jan Bugajski

Department of Physiology, Institute of Pharmacology, Polish Galanin is a peptide identificated in the CNS of humans and Academy of Sciences, Krakow, Poland different species of animals. Galanin exerts modulatory effects The significance of prostaglandins (PG) and nitric oxide (NO) in the on different central neurotransmitter systems. We tried to hypothalamic-pituitary-adrenal (HPA) response to vasopressin (VP) was reveal the possible interaction of galanin with the different investigated in rats crowded for 3 days. We have found that vasopressin neurotransrnittive systems in the CNS. is almost as potent as corticotropin-releasing hormone (CRH) in Experiments were performed on male CFY rats. Rat galanin stimulating the HPA axis. Social crowding stress considerably diminished the ACTH and corticosterone response to VP but not to CRH or (2,10,50 ng) was admistered intrasbiatally (is.) either alone interleukin-lo. Indomethacin, an inhibitor of constitutive cyclooxygenase or 10 min after kainic acid (KA) admmistration (20-100 ng). (COX-1) and PG synthesis significantly reduced the ACTH and Naloxone (1.0 mg\kg), ketamine (5.0 mg\kg) and atropine (1.0 corticosterone response to VP in control rats and further reduced this mgikg) were used i.p. 10 min prior to KA or galanin. We response to VP already diminished by crowding stress. Dexamethasone (DEX) abolished the HPA response to a short restraint stress and the investigated the locomator activity in the "open field test and response to VP in both control and crowded rats. Although DEX inhibits muscle tonus. the HPA axis by negative feedback mechanisms it also inhibits the We revealed the development of KA-induced bradykinesia, induction of COX-2 and nitric oxide synthase (NOS). Nitric oxide synthase ptosis and muscle tonus increasing. Galanin coadrmnistration is present in perikarya of the hypothalamic nuclei closely associated with the regulation of pituitary activity, in the median eminence and the with KA (20 ng) into the striaturn dose-dependently resulted in pituitary itself. A nitric oxide synthase antagonist Nw-nitro-L-arginine- the development of behavioral disturbances reminiscent of methylester (L-NAME) significantly enhanced, and L-arginine, a NO those obtained after KA i.s. admmstration. Named behavioral donor, considerably diminished the HPA response to VP or stress, disturbances were partially blocked by naloxone, ketamine or indicating that NO inhibits centrally the HPA stimulation. The results indicated a significant interaction of PG and NO systems in atropine. It is concluded that galanin potentiates the action of activation of the HPA axis by VP during stressful circumstances. is. KA in inducing of specific behavioral impairments. This effect can be realized via galanin lnodulatory effects on the opiate, excitatory amino acids or cholinergc transmission.

EFFECTS OF ANGIOTEYSIN I1 AhD ITS PEPTIDE 4ND Effects of peptide and nonpeptide angiotensin I1 receptor NONPEPTIDE RECEPTOR AhTAGONlSTS Oh 4 WRITHING TEST antagonists on acute hypoxia in mice. D.Georg~evaand V.Georgiev M.Opitz and V.Georgiev (Laboraton 'Eup Ps\chophannacolog\' , Inst~tute of Ph\ slolog\, Laboratory "Exp Psychopharmacology", Inst~tute of Phys~ology, Bulg Acad SCI Acad G Boncheb Str B123 1 113 Sofia Bulgaria) Bulg Acad SCI, Acad G Bonchev Str , BI 23, 11 13 Sofia, Bulgar~a

The \\r~thlngtest (acetlc acld 1 '4 ~p)was used Wr~thlngs\\ere counted at 5 The effects of i c v administered ang~otensinI1 (AT 11) peptide receptor min ~ntenalsfor 30 mlnutes 4nglotensln 11 (4TII) at doses of 0 1 and I pg IC\ antagonists saralasin (Sar) and sarmesin (Sarm), as well as of nonpeptide s~gnlficantl\ decreased nrlth~ngsn~thln all 10 mln perlod AT11 analogue receptor antagonists DuP 753 and PD 123319 on acute hypoxia saralas~n(0 i pg 1c1)decreased wrlthlngs onl\ ulth~nfirst 5 mln and Increased (asphyctic and haemic - sodium nitrite 300 mglkg, s c ) were studied in them wlthln 10 mln Pretreatment of saralasln blocked the effect of 4TII (0 1 male mice Latencies (in min) until the first clonic seizures and an~mal pg) at 15 mln AT11 analogue sarrnesln - [s~~'T~~"(M~)]ATI~(0 5 1 5pg death (survival time) were measured as end points of hypoxia It was IC~),decreased wrlthlngs durlng the whole 30 mln obsened perlod u~tha dose of 5pg Sannesln (0 5 pg) blocked the effect of AT11 (0 1 ~g)from 10th to 30th found that both Sar (1, 5, 10 big) and Sarm (1, 5, 10 big) increased mlnutes The non-peptlde AT receptor antagomst DuP753 (25 i0pg) shoned latencies until seizures the survival time (asphyctic hypoxia) In haemic well e~pressedanalgetlc effect DuP751 (25 pg) dld not block the analget~c hypoxia only Sar in the dose of 10 pg increased the two studied effect of AT I1 (0 1 ug) The non-pzptlde AT receptor antagonlst PD 1233 19 parameteres and Sarm did not influence them DuP 753 (50. 100, 200 (5 10 pg) showed alget~ceffect (Increased number of \\rlthlngs) at 10th and l.lg) increased latencies until seizures and the survival time (both types of 15th mln PD 1233 19 blocked the analgetlc effect of AT11 (0 1 pg) Taken hypoxia) PD 1233 19 (5. 10, 20 pg), also influenced both parameters in together ~trnlght be accepted that AT11 reallzes ~tsanalget~c effect on wrlthlng asphyctic hypoxia and decreasing them in (haemic hypoxia) Taken test through AT receptor subtlpe together. the results show that the balanced participation of both ATI Acknowledgements Thls work was supported b\ EC through the and AT2 receptor subtypes is necessary for regulation of acute hypoxia COPER4ICUS programme contract No C IPA CT 94-0219 and b\ Grant L- Acknowledgements This work was supported by EC through the 526 from the Nat~onalFund ' Sclentlfic Research at the Bulgarian Mlnistn of COPERNICUS programme, contract No CIPA CT 94-0239, and by Education Sc~enceand Technolog\ Grant L-526 from the National Fund "Scientific Research" at the Bulgarian Ministry of Education, Science and Technology Tuesday, Poster session: Motor control 63

Poster session - Motor control

CHANGES IN LOCOMOTION AFTER PARTIAL SPINAL LESIONS IN SURVIVAL AND GROWTH OF EMBRYONIC CELLS FROM RAPHE RATS NUCLEUS TRANSPLANTED INTO TRANSECTED SPINAL CORD IN W. Zmyslowski', T. Gorska, H. Majczynski, B. Chojnicka RATS. 'Institute of Biocybernetics and Biomedical Engineering and Nencki Institute of U. Slawsska, H. Majczynski', R.L. Djavadian' Experimental Biology, Polish Academy of Sciences, Warsaw, Poland. Institute of Biocybernetics. and Biomedical Engineering. 'Nencki Institute of Experimental Biology, Warsaw, Poland. In 7 intact rats and 5 rats with partial spinal lesions, performed at the low thoracic level, the main indices of gait during unrestrained locomotion were Recently, fetal neuronal transplants have been used for supplying new cells compared. The animals were taught to move on 2 m long and 12 cm wide for anatomic and neurophysiologic integration into the host CNS to restore lost platform placed 1.5 m above the ground. The platform was covered with function. In our experiments the circuitry of the spinal cord (central pattern conductive material connected to low voltage DC source. The an~malswore on generators - CPGs) involved In producing locomotor movements of hindlimbs palmar surface of each limb small cooper wire contact electrodes, which allowed was separated from the supraspinal inflow by transection of the spinal cord at to record the stance and swing phases of each limb. The locomotion velocity the lower thoracic level (Th9-ThlO). Following spinal cord transection, the was measured using photocells placed every 25 cm. In the operated group, in CPGs, although still present in the disconnected part of the spinal cord, were 3 rats the lesion was essentially confined to the dorsal columns, while in the unable to generate coordinated movements. One of the main reasons of hindlimb remaining 2 animals it was much larger, involving dorsal quadrants of the spinal movement deficits is a destruction of supraspinal monoaminergic pathways cord. The operated animals with smaller lesions were tested both before and which are known to influence the CPGs activity responsible for producing after surgery, while the animals with larger lesion were tested only locomotor movements. Recent results show that administration of postoperatively. No essential changes were found between pre- and postoperative monoaminergic (serotonergic and noradrenergic) agonists to spinal cats improves data in rats with smaller lesions, nor between the animals with lager lesion and their locomotor performance. In order to administrate serotonin to the the group of intact animals with regard to locomotor velocity, swing, stance and disconnected spinal cord in rats, the embryonic tissue of raphe nucleus region step cycle durations in the fore- and hindlimbs, the lateral and diagonal phase (containing serotoninergic cells) was transplanted one months after spinal cord shifts and their relationships with the step cycle duration. The coupling of the transectlon. fore- and hindlimb movements, measured by the correlation of time intervals Three months after transplantation, the rats were deeply anesthetized with between the onsets of each limb stance phase and the offsets of these phases in injection of sodium pentobarbital (6OmgIkg) and perfused transcardially with the homologous and the diagonal limbs, were not changed in animals with 0.9% saline followed by 4% paraformaldehyde. After dissection, the spinal cord smaller lesions, while in the 2 animals with larger lesions, it was less accurate was prepared for further immunocytochemical treatment in order to establish the as shown by weaker correlation between the measured time intervals. This grafts survival. The 40 pm cryostat sections of the spinal cord were processed means that in latter animals the movements of the hindlimbs were less dependent for immunocytochemical detection of serotonin (5-HT). The transplanted rats on the movements of the forelimbs than in the remaining operated animals. Our showed many immunoreactive 5-HT perikarya in the graft area, some at a results show that neither dorsal columns nor the dorsal quadrants are not distance of up to 15mm, and a progressive innervation of the whole grey matter essential for locomotor movements, although the latter lesion impair some extending over at least 20mm from the graft site. indices of fore- hindlimb coordination. Our behavioral experiments showed the improvement of motor function which may confirm that the grafted cells of embryonic raphe nucleus, after integration with the host neuropil, are able to release serotonin into the separated part of the spinal cord and to encourage recovery of hindlimb locomotor functions.

PARTIAL RESTORATION OF HINDLIMB FUNCTION IN ADULT SPINAL THE INVESTIGATION OF MOTONEURONAL CHARACTERISTICS RATS AFTER TRANSPLANTATION OF EMBRYONIC RAPHE NUCLEUS IN HUMAN INTO THE SPINAL CORD BELOW THE TRANSECTION. Maria ~iotrkiewicz',Lydia ~udlna~,lrena ~ausmanowa-petrusewicz3. U. Slawitiska and H. Majczyhki' Natalia .Zhoukovskaya2,and Jolanta ~ierzejewska' Institute of Biocybernetics and Biomedical Engineering, 'Nencki Institute of Institute of Biocybernetics and Biomedical Engineering. PAS, Warsaw Experimental Biology, Warsaw, Poland. 21nstitute for Problems of Information Transmission, KAS, Moscow 3~euromuscularUnit, Medical Research Center. PAS. Warsaw Monoaminergic pathways are known to influence the circuitry of the spinal cord involved in producing locomotor movements (central pattern generators - CPGs). The relationsh~pbetween two characteristlcs of human motoneurons, Following spinal cord transection, the CPGs, although still present in the discon- the aflerhyperpolarizatlon (AHP) duration and the relationship between the nected pan of the spinal cord. are unable to generate coordinated movements. standard deviation of the interspike intervals (ISls) and thelr mean value, Administration of serotonergic agonists to spinal cats improves their locomotor s(T,,,), was studied ~n two serles of experiments. During the first one, the movement. Another method of administering serotonin to the spinal cord is by rhythmic firing of voluntarily activated single MUs of two muscle types: fast grafting of embryonic cells from raphe nucleus. The aim of our study was to acti- - biceps brachii (BE) and slow - soleus (SOL). was recorded and stationary vate the CPGs by using the grafted cells which were supposed to release serotonin. fragments were analyzed off-line to get their statistical characteristlcs. In The graft of embryonic, serotoninergic cells survives transplantation and the second series of experiments, the tibia1 nerve was stimulated with integrates with the host neuropil. Moreover, the grafts seem to encourage paired stirnull of varied interpulse interval. Responses of single MUs from functional improvement. Our study showed that the embryonic tissue transplanted SOL were recorded and the AHP duration was estimated from the recovery period of the motoneuronal excitability afler the first stimulus. into the separated pan of the spinal cord one month after its transection at the Th9- The relationships s(T,) of single MUs were slightly different from those 10 level resulted in more coordinated hindlimb movement of Wistar rats. Three reported in the literature for the pooled data. The plateau for shorter months after transplantation the funct~onalimprovement of motor function was intervals was scarcely observed. Instead, the typlcal relationship for a assessed by behavioral and electromyograpbic analys~s.Locomotor activity was single MU consisted of two segments of a straight line with different slopes. tested in animals held with their forelimbs on the moving trolley and their Some of the relationships for MUs from BB could not be approximated by hindlimbs walking on the pathway with simultaneous stimulation of the tail. A two straight lines but were curvilinear. There was a significant scatter of rhythmical locomotor activity with a pattern similar to that observed in intact the break-points for MUs from the same muscle type of all subjects and animals (alternating movements of right-left hindlimb and complete flexion- even for MUs from one subject only. As expected. the range of the break- extension movements) was regularly obtained in grafted rats. Although, some points for BB was shifled towards the shorter lSls as compared to SOL rhythmic alternating movements were also observed in spinal animals (without For SOL MUs, the break-point range corresponded to the intervals shorter graft), the coordination between the hindlimbs was improved in the grafted spinal than the range of the AHP duration. animals. The electromyographic activity recorded from soleus and tibialis anterior The results presented above provide evidence that the statistical muscles during regular locomotion showed a typical alternating pattern of extensor parameters of a single MU activity are dependent on the motoneuron and flexor activity. However, unlike in intact animals, in the grafted rats the burst properties. These properties for a motoneuron pool of a given muscle are duration of the flexor muscle was related to the step cycle durat~on. not uniform. The results seem to indicate that transplantation of defined groups of neurones The correlation between the statistical parameters of the MU activity to the transected spinal cord made use of the residual circuitry in the lesioned and the AHP duration established in this study may be significant for spinal cord to improve the recovery of motor functions after lesions. clinical studies of neuromuscular diseases The differences in this respect were recently revealed to exist between dystrophic and normal muscles. 64 Tuesday, Poster session: Motor control

SOLEUS DISTINCTIONS IN CLINICAL DIRECTIVITY OF INFORMATION FLOW BEnVEEN LIMBIC AND MOTOR ELECTROPHYSIOLOGICAL EXAMINATIONS STRUCTURES FOR VARIOUS FREQUENCY BANDS IN MOVING RAT

D Wochn~k-Dyjas,Cz. Glazowsk~,M N~ew~adomska Dept. of Newophys ,Nencki Institute of Exp Biol., Pasteura 3 Str., Warsaw, 02493, Poland Investigation of functional role of limbic-motor connections involved in emotional Inst~tuteof Psychlatry and Neurology,Department of Clln~cal behatior and initiating the performance of motor reaction was the aim of our ex- Neurophys~ology,Al Sob~esk~ego119, 02-957 Warsaw, Poland periment. Information flow among a nodal point behveen the motivational and executor). ?stems in the brain - the n. accumbens (ACC), its main input structures the basolateral amygdala (BLA) and ventral subiculum (VSB), and its output to the Motor evoked potent~als(MEPs) were recorded by transcran~al motor system, the subpallidal area (SPL), nas analyzed. The EEG signals, recorded magnetlc st~mulat~on(TMS) comb~ned w~th electr~cal ~tithcluonic electrodes in various experimental situations (emotional states) in freely st~mulat~onof pert~nent pher~pheral nerves Th~sprocedure mo~ingrats, were analyzed nith the use of directed trander function (DTF). The allows to estlmate central conduction In segment. cortex-sp~nal method enabled analysis of the direction and intensity of information flow among structures, taking into account all signals simultaneously, and providing qxtd motoneurones (CCT-F). Four muscles of low l~mbs:VL, TA, characteristics of information flow among structures. The DTFs \yere normalized in EDB and SOL were examined bilaterally at rest. (240 muscles a nay enabling comparison of information flow for various beha\ioral situations in 6 In 30 healthy subjects) From theoret~calpolnt of mew CCT-Fs selected frequenq bands from the range of 1-90 Hz. Thus, we estimated the differ- ences of the strength of information flow nithin the BLA-VSB-ACC-SPL circuiw, should be success~velylonger depend on descending metamerlc and as a result we obtained a pattern of connections for which flows in various local~sat~on of motoneurons ~nnervatlng exam~ned situations were different. Comparison of DTFs for the rest state and well trained muscle However CCT-F for SOL revealed to be relat~veshort locomotion (i.e., a low emotional state) showed that the flows for frequencies above Moreover the mean ampl~tudeof ,,cort~cal"C-MEP from SOL 30 Hz did not differ for both situations. Most of the differences were present in the theta band (7.9-9.3 Hz), the interactions among all structures were siguticantly was relatively the smallest one In comparison w~ththe C-MEPs higher during locomotioq when compared nith the rest state. During the preparatov from other muscles On the contrary the ampl~tudes of phase to locomotion the flow from all strumto ACC was higher than in the rest per~pheral CMAP and F-wave were the h~ghest ones state, while after the locomotor). phase the flow behveen ACC and SPL nlls the same Standanzed dlstal motor latency (DMLlcm) was In SOL the as in the rest state. During maze exploration some of the flo~vsin the theta band were also higher, when compared to the rest state. In the band of 67.7-72.2 Hz the com- longest D~fferenceswere statistically s~gnrficant.The cause of parison of the DTF values cal~datedfor various experimental situations shoved that SOL distmct~onsmay be explained by different structure and they mere different for exploration of maze in comparison with the locomotion along ~nnervatlonof th~smuscle (slow - red, tonlc muscle) a aide mtay. Inducing the bell stimulus during locomotion on a wide runway resulted in changes of the DTF values for the information flow from ACC to SPL only. Summarizing the results one can say that patterns of information flow among structures are different for various kquency bands, depending on the experimental situation (i.e., emotional-motivationaland motor components of the task).

Lesions of the anterior intraparietal area induce prehension deficits Ferdinand inko of ski', Christian ~ohle', Stefan posse2, Harald ~efter',Rudiger J Seitzl, Hans-Joachim ~reund' '~epartmentof Neurology, University of Dusseldorf, MoorenstraBe 5, D-40225 Dusseldorf, Germany, 2~nstituteof Medicine, Research Center Julich GmbH, D-52425 Jiilich, Germany Recently, it has been shown in non-human primates that the posterior parietal cortex is involved in coordination of arm and eye movements in space, while the anterior lateral bank of the intraparietal sulcus (anterior intraparietal area, AIP) plays a crucial role in grasping. In this study we show by kirierr~aticrecordings that patients with cortical lesions involving the anterior part of the intraparietal sulcus and the human homologue of AIP have selective deficits in the coordination of finger movements required for object grasping whereas the reaching is much less disturbed, fMRI data obtained during reaching and grasping movements provide complementary evidence that the same area is specifically activated during grasping. Taken together, the combined lesion and activation study is suggestive that AIP mediates the processing of sensorimotor integration of precisely tuned finger movements in humans. Tuesday, Poster session: Sensory processing 65

Poster session - Sensory processing

CHANGES OF EVOKED POTENTIALS INDUCED IN THE IMMEDIATE CHANGES OF INTRACORTICAL INFORMATION SOMATOSENSORY BARREL CORTEX BY COOLING PROCESSING RELATED TO THE CONDITIONTNG PROCEDURE

P. Musial, E. Kublik and A. Wrobel

E. Kublik, P. Musial and A. Wrobel Department of Neurophys~ology, Nencki Institute of Experimental Biology, 3 Pasteur Str., 02-093 Warsaw, Poland It is known that low temperature inhibits electrical actlvity of the cortlcal tissue. We ut~lizedthis mechan~smto evaluate contribution We used for this study five unanesthetized rats with chronic of various populations of cells In barrel cortex into the potential evoked electrodes implanted in the barrel cortex. Before recording animals were (EP) by vibrissae stimulation. trained to rest in a plexiglass tube with head restrained in a holder. After implantation of electrodes the chosen vibrissa was stimulated with piezoelectric device and evoked potentials (EP) were recorded from the Three hooded rats were used in the expenments. Under urethan barrel cortex. Five habituation sessions were followed by a conditioning anaesthes~athe scull was opened to expose the barrel field. The sesslon and in all of them the animal received 100 vibrissa stimulations multichannel electrode was then placed Into the cortex at the depth of wlth intervals randomly scattered from 30 to 45 s. In the conditioning 0, 300. 600 1200 pm from the surface. The silver plate attached to session the first 30 vibrissal stimulations allowed for stabilization of the narrow plastic tube was placed on the surrounding surface of the barrel EPs. All remaining stimulations were followed by a mild electric shock field around the electrode. By stroking each v~brissa with the (uncond~tioningstimulus) applied with a 250 ms delay to the ear on the p~ezoelectricdevice we recorded evoked potentials (EPs) to obtaln four same slde. The whole conditioning session lasted for about an hour. maps of EP amplitudes associated with each recording site of the The first negative component (Nl) of EP consisted of two peaks electrode. The principal whisker (PW) - corresponding to the biggest EP with latencies differing by 1.5-2 ms. The contribution of these subcomponents of N1 to the integral value of EP was calculated w~thin - was then cont~nuouslystimulated with a 5s interstimulus interval and the 5 ms period containing both peaks. This procedure allowed to classify the EPs were on-line d~g~tizedand stored on PC computer by the Sp1ke2 EPs with respect to relative amplitude of the two subcomponents. The software. The "Freeze 75" was sprayed Into the plastic tube In order to second class differed from the first one by increased amplitude of the cool the s~lverplate and the underlying cortex. This method allowed to second subcomponent. Introduction of the conditioning procedure lower the temperature rapidly and deactivate the cortex throughout the changed the control ratio of the two classes in such a way that number of EPs with the enhanced amplitude of later subcomponent rapidly whole its de~th.This ~rocedureresulted in disa~~earanceA A of EPs followed by their slow restitution with the Increasing temperature. After increased. We hypothesize that the two N1 subcomponents might reflect the a few seconds EPs reappeared with amplitudes comparable to control successive stages of sensory information flow within the barrel cortex. but with twice as long latencies. The control shapes of EPs were The conditioning procedure would recruit larger population of cells at the observed only after a few m~nutes. higher processing level (delayed by one synapse) and thus enhance the amplitude of the second subcomponent.

VISUAL TASK STIRS CORRELATED ACTIVITY IN CAT'S INTERACTION BETWEEN NITRIC OXIDE SYNTHASE THALAMO-CORTICAL SYSTEM AND OXOTREMORlNE IN ACUTE AND CHRONIC PAIN. D. Krakowska, W. Waleszcmk, M. Bekisz and A. Wrobel. Nencki Institute of Expenmental Biology, 3 Pasteur St., 02-093 Warsaw, Poland J Mika. F Capone*. H Machelska, D. tabu. F. Payone*, B. Pr~elvlocka. We have previously shown (Bekisz and Wrobel, Acta Dept of Molecular Neuropharmacology. Inst. of Pharmacology. Krakow. Poland . * Inst of Psychobiolog! and Psychophar~nacologyCNR. Rome, Italy Neurobiol. Exp. (1993), 53: 175-182) that local field activity (LFP) recorded from many sites in lateral geniculate nucleus (LGN) and The present research uas a~liledto find out. using behavioral and primary visual cortex (VCx) of cats attending to visual stimuli during 1i~u1~1unol1istoc1~em1calmethods. shether the cholinergic analgeaa Induced by conditioning task contalned enhanced amount of power within 20 Hz the muscartnic agonist oxotrenlorine uas modulated by nitr~coxide in different band as compared to auditory or erroneously ended visual tnals. tests of nocicept~on.The prel~~n~naryexperiment showed that intraper~toneal We now analyzed the same data by calculating the normalized adluin~strat~onof the nitr~comde s!nthase inhibitors NG-n~tro-L-arginine- cross-correlation coefiicient with zero lag (CC) for (I) band-pass filtered methql ester (L-NAME) and NG-n~tro-L-arginine(N-ARG) in doses ineffective (16-24 Hz) LFPs and (2) ampl~tudeenvelopes of these filtered signals, per sc sign~ficantlqenhanced the analgesic effect of oxotremorine in CDI mice In a tail-fllck test MorcoTer. an interact~onbetneen oxotrcmorine and NO was for all possible pairs between recording sites. also reported \\lien the effects of those drugs Irere stucbed at a spinal level. The analysis revealed positive synchronization between filtered lntrathccal adniinistrat~nof L-NAME (400 pg) increased the antinociceptive signals from majonty of electrodes during nonv~sualsituations which actlon of ovotremorine (Ing) In both the paw pressure and tall flick tests in indicated common osc~llatoryrhythm within the investigated part of the W~starrats visual system. The level of synchronization decreased during periods Wc also inyestigated the interact~on between L-NAME and involving visual attention. In few pairs of recording sites of CC>0.8, the oxotrernorlne In tilodulation of the response to a prolonged nociceptive st~mulus synchron~zationof such an actlvlty Increased S~m~lard~rection of CC Induced b> ~ntraplantar injection of formalin to rats. Behavioral and ~mtnunohistochemicalmethods aere used changes were obtamed when calculating the amplitude envelopes for the Intraplantar forn~al~n injection significantly enhanced the glven palr of electrodes We therefore conclude that maln contribution character~st~cbehaviour (pan jerks) and Increased the nun~berof NO synthase to CC values is from simultaneous, large amplitude bursts w~th~n-phase labelled neurons in laminae 1-111. IV and X. but not in laminae V-VI. osc~llationsand not from continuous synchron~zationof phase between Ovotremor~neand L-NAME lnh~bltedthe paw-jerk frequency. howeyer only in both slgnals the second phase of the forlnal~n-inducedbehavior. Both oxotremorine and L- We hypothes~ze that vlsual attention activates the speclfic NAME suppressed the formal~n-inducedincrease in the nun~berof NO synthase neurons. maml! on the psil lateral side of the lumbar spinal cord. mosaic of functional connections mith the use of the 20 Hz osc~llatory In summav. our stu* suppons the h3pthesis that inhib~tionof NO synthase camer Thls activation changes the baslc, global synchronization into in the spinal cord may facilitate ant~nocicept~onAt the same tlme. we have also organized v~sualnetwork for the process off attentlve seeing obtained some ev~dencethat oxotrenlorine may either increase or reduce the the number of NO s~nthase-labelledneurons In the formalm model Thr\ >fork uny crrpporfe(1hi ~totufownclrvrhhv hBI' Ilnrsn1+ 66 Tuesday, Poster session: Sensory processing

ANTINOCICEPTIVE EFFECTS OF HYPOTHALAMIC Effect of acoustic stimulus characteristic on REWARDING STIMULATION IN THE FORMALIN startle response in rats TEST IN YOUNG AND ADULT RABBITS Janusz W. Bkaszczyk and Katarzyna Tajchert I.P.Butkevich, V.G.Kassil, V.A.Mikhailenko Laboratory of Ontogeny of Higher Nervous Activity, I.P. Nencki Institute of Experimental Biology, Pavlov Institute of Physiology, Academy of Sciences of Warsaw. Poland. Russia, St. Petersburg, Russia The startle reflex is an animal response to a In 20-25-d-old and adult rabbits anaesthetized with sudden intense stimulus e.g. sound pulse. The urethane and chloralose the inhibitory effects of electrical acoustic startle response (ASR) depends not stimulation of hypothalamic reward sites on the evoked only on the pulse amplitude but is also modulated by a stimulus frequency. In the potentials (EPs) recorded in the thalamic intralaminar nuclei experiment amplitude and latency of the in response to the electrodermal stimuli applied to the acoustic startle reflex were assessed for a hindpaw were investigated before and after injection of variety of stimulus frequencies ranging between dilute formalin (F) in the contralateral hindpaw. Before F we 3 and 23 kHz. The responses were studied in 11 determined the intensity of rewarding stimulation that adult hooded rats by means 2-ms tone pulse of induced the decrease of amplitude of EPs but not their different frequency presented without or with complete inhibition. F produced the biphasic (in 5-10 min 70 dB white noise background. A main effect for frequency was found with responses to low and 20-60 min after injection of F) enhancement of the frequency stimuli. Analysis of the ASR inhibitory effect of rewarding stimulation manifesting as the amplitude for each testing frequencies showed complete inhibition of EPs recorded in response to significant differences (F(5,50)= 48.375, electrodermal stimuli applied to the contralateral P

THE SPATIAL STRUCTURE OF THE VISUAL RECEF'TNE FIELDS OF CAT'S PRETECTAL NEURONES W. Waleszczyk, K. Dec, Department of Neurophysiology, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland The aim of this study was to examine spatial organization of the receptive fields of visually sensitive neurones in the pretectal region. The 21 neurones was examined using extracellular recording of single units in the pretrigeminally transected cats. After establishing the preference for the stimulus size and velocity of movement, cells were tested with a decreasing range of stimulus movement around the centre of the receptive field and with a small range of movement around the locations placed in equal intervals along the horizontal axis of the receptive field. The intensity of cellular responses varied depending on the range of the stimulus movement and the location within the receptive field. The intensity of responses gradually decreased with the decrease of the range of movement. The majority of units required a quite large range (2.5"- 20") of the stimulus movement to evoke the~rresponse. Only one neurone responded to the range as small as lo. The smallest range of the stimulus movement was achieved for a preferred stimulus size and velocity of movement and could differ between ipsi- and contralateral eye inputs. The majority of cells did not change their directional selectivity with a decreasing range of the stimulus movement. Only one out of all tested cells showed changes in the directional selectivity index depending on the location of the stimulus within the receptive field. The pretectal cells require large region of summation to evoke the response and show high level of homogeneity of their receptive fields. These properties of receptive fields of neurones in the pretectal region distinguish them from highly heterogenous receptive fields of collicular cells which are unusually sensitive to small range of the stimulus movement. Tuesday, Poster session: Learning, memory . . . 67

Poster session - Learning, memory and cognitive functions

CHOLINERGIC MODULATION OF LONG-TERM THE ROLE OF NMDA RECEPTORS IN ACTION OF ARGININE- DEPRESSION IN HORIZONTAL CONNECTIONS OF RAT VASOPRESSIN AND ANGIOTENSIN I1 IN LEARNING AND MEMORY MOTOR CORTEX Konstanty WiSniewski. Barbara Attemowicz R Krawczvk and G. Hess Institute of Zoology, Jagiellonian University, Ingardena 6, 30-060 Department of Phasmacolog> Med~calAcademq, Mlcklewlcza 2c. 15-222 Krakow, Poland B~alystok.Poland Recent studies indicated that the activation of cholinergic receptors may play a role in the induction of long-term increases of Date from literature indicate that ionotropic receptors of glutaminergic system - NMDA receptors play a role in central action of neuropeptides, especially in synaptic efficacy in certain cortical areas. Here we have investigated learning and memory processes. We studied the influence of various antagonists the influence of cholinergic activation on the threshold of long-term of NMDA receptors on effects of arginine-vasopressin (AVP) and angiotensin I1 depression (LTD) in local horizontal connections within layers IIim (All) improving learning and memor). in rats We used the following of rat motor cortex, using field potential recording in brain slices In compounds: competitive antagonist - AP-7, noncompetitive - MK-80 1, vrtro. In standard incubation conditions 1500 pulses applied at 3 Hz antagonist of polyamines site - arcaine and antagonist of glyclne site - HA-966 in these processes The experiments were carried on the male Wistar rats. All routinely induced LTD (-25k15% decrease, n=6), measured 20 min compounds were injected ~ntracerebroventr~cular).(the antagonists 15min before after cessation of the stimulation. The application of 1000 pulses neuropeptides). induced only small changes (-1054%, n=6), and 500 stimuli We have shown that: delivered at 3 Hz did not produce any marked changes in the 1. Mk-801 signiiicantly reduces the acquisition in conditioning avoidance responses (CARs), whlch wasincreased by A11 and decreases the beneficla1 response amplitude (n=3). In contrast, 1000 pulses applied in the effect of AVP on the consolidation in CARs. MK-801 diminishes the presence of a cholinergic agonist, carbachol(0.5 phi) in the bathing adventageous effect of A11 on acquisition and remembering in passive avoidance fluid, induced marked LTD of responses (-2033%, n=5). The effect situation. 2 AP-7 impairs the action of A11 on the acquisition of CARs, acquisition and of 1500 pulses applied in the presence of carbachol (-25k4%, n=5) remembering in passlve avoidance responses. AP-7 does not change of action of was not different from control. AVP. These results, together with an earlier communication (Hess 3 Arcaine significantly dimmishes the effects of AVP on the remembering in and Krawczyk, Eur. J. Neurosci. Suppl. 9: 201, 1996), suggest that passive avoidance behav~orand decreases the effect of A11 on the acquisition. cholinergc modulatory effects may facilitate plastic synaptic 4 HA-966 diminishes, but not slgnlficantly, effects of vasopressin on the remembering In passive avoidance responses and does not Influence on the rearrangements wihhorizontally directed intrinsic pathways of rat effects of AVP on the consolidation In CARs. In used doses no compound motor cortex. change the motor actlvlty of animals in open field test Support: KBN grant 6P04C 053 08, HHMI grant 75 195-543-101

THE CO\TRIBUTIO\ OF AT? ANGIOTE\SIN RECEPTORS TO EFFECTS OF AT II AND ITS RECEPTOR ANTAGONISTS THE COG\ITIVE EFFECTS OF ANGIOTENSlh I1 AND ITS 3-7 FRAGMENT (PEPTIDE AND NON-PEPTIDE) ON MEMORY PROCESSES OF RATS. J.J. Braszko. A Kulakouska*. W. Karwowska-Polecka** V.Georgiev and T.Karnbourova Clinical Pharmacolog? Unit. *Department of Neurolog).. **Department of Lab."Exp.Psychopharmacology", Inst.Physiology, Bulg Acad. Pharmacolog~.Medical Academy of Bialystok, Kilidskiego 1 . 15230 Bialystok. Poland Sci., 1113 Sofia, Bulgaria

\Ve have previously show that angiotensin I1 (Ang 11) and its 3-7 fragment The effects df AT II (0.1, 0.5 and 1 pg) and of its peptide [Ang II(3-7)] facilitate acquisition and recall of certain behaviours in rats. receptor antagonists saralasin (1 and 5 pg) as well as In this study we assessed the role of AT2 angiotensin receptors in the nonpeptide receptor antagonists for AT, subtype DuP 753 (50 cognition enhancing activity of both peptides using selective AT2 receptor and 100 ~g)and for AT, subtype, PD 123319 (5, 10 and 20 pg) inhibitor PD 1233 19 (I-[[4-(dimethylaminoj-3-methylphenyl]methyll-5- were studied through passive avoidance (step through) and (diphenylacet) 1)-43.6.7-tetrahydro- IH-imidazo[4,5-clpyridine-6-carboxylic active avoidance (shuttle box) paradigms on male albino rats acid: PD). Male Wistar rats (160-180 g). after surgical preparation. were given into the left lateral cerebral ventricle. 2p1 of 0.9% NaCl with or by i.c.v. administration made immediately after the last training uithout 1.5pg of PD. Five min later the animals mere given. into the right session. AT II (0.1 l~g)lead to improvement of retention at both cerebral ventricle. 2p1 of 0.9% NaCl with or without 1 nmole of Ang I1 or paradigms tested 24 h and 7 day after training. Peptide and Ang II(3-7). Follouing the next 15 min recall of a passive avoidance. non-peptide AT II receptor antagonists did not induce any acquisition of an conditioned avoidance responses (CARs). apomorphine changes on retention both at 24h and 7 day after training (1 mg~kgi.p.) stereobpy. anxiety in the elevated 'plus' maze. and motor procedure, in both paradigms; however they antagonized the activit) in an 'open field' uere evaluated. Also,the discrimination rate effects of AT II. Taken together, the results show the balanced bemeen some familiar and unfamiliar objects was assessed 60 min after participation of AT II receptors (both AT, and AT ,subtypes) in the second intracerebroventricular injection (recognition memory). regulation of memory processes. Pretreatment of rats with PD. inactive on its omin all tests. diminished the Acknolwled~ement.This study was supported by European improvement of recall and recognition memory caused by Ang I1 and Ang I1 Community through the COPERNICUS programme, contract (3-7). It also abolished enhancement of stereotypy and increased rate of No ClPA CT 94-0239 and by Grant L-526 from the National CARs acquisition by the peptides. In the elevated 'plus' maze PD only Fund ,,Scientific Research" at the Bulgarian Ministry of partially diminished anxiogenic action of Ang 11. No statistically significant Education, Science and Technology. effects were obtained in 'open field' except for some decrease by PD of motor activit) in Ang I1 pretreated animals. It appears that memory improving activit) of Ang I1 and Ang II(3-7) is mediated by similar mechanisms and AT2 receptors are substantially engaged in these processes 68 Tuesday, Poster session: Learning, memory . . .

THE EFFECT OF IS.3R-ACPD ON COGNITIVE PROCESSES AFTER CATECHOW~iINERGICBRAIN SYSTEM AND SEHAVIOR BLOCKADE OF NMDA RECEPTOR IN RATS. OF HATS WDH DIFFERFNT EMOTIONAL RFACTNITY Ttl STRESS Konstanty Wiiniewski, Alicja Zalewska Ismailova Kh.Yu. ,Scmenova T .P. Institute of I'hysiology of Acad.Sci.,Eaku, Department of Pharmacology, Medical Academy of Biafystok, 370100,dzorb~iijan Mickiewicza 2c, 15-222 Biafystok, Poland On sale '.'/istar rats with different emotional reactivityoto acoustic stressful stir:iulus the We have previously shown that 1-amino-cyclopentano-1,3-dicarboxylic effect of da::iage of catecholarninergic (Cx) acid (1S,3R-ACPD), an agonist of metabotropic glutamate receptors brain structures (6-oxydopha~iiine(5-OM) ,intra- improves learning and memory in a passive avoidance situation. In this ventricularly ,1508) on realization of a nurabzr study we attempt to asses the role of NMDA receptor in cognitive of inborn and acquired behavior form and bra- effects of 1S,3R-ACPD. The compound was given 30 min before in biogenic amines (EA)turnover are stu6ied. In both ijroups of rats 8 emotional-nonreactive learning trial when its influence on acquisition was tested, and (ZILTH) and emo tional-re act ive (Ad) the influen- immediately after it for the evaluation of its influence on consolidation ces of toxin decrease of orienting-ex?lorato- processes. 30 min before intracerebroventricular (icv) injection of 100 ry activity in "open f ieldt'test, "holeboard" nmole of 1S,3R-ACPD, half of the animals received icv AP7 (10 nmole), test, reactivity to sensory stinuli(tactile, or MK-801 (5 nmole), competitive and non-competitive antagonist of v~sual,olfactory),chan~esof learning aroces- NMDA receptor, respectively. Control animals were icv injected with ses of conditional-food-directed r'2action 0.9% NaCI. Retention of a passive avoidance behaviour was tested 24 h are ol~served. The degree of changes of this after the learning trial. In addition, evaluation of the locomotor and index is more pro~rinentin SIX ~-atsin coLqa- rison to $11. The more pronouce3 decrease of exploratory activity in open field was conducted in all groups of rats 2 h exploratory activity in iMH rats is correlated prior to the retention testing. 1S,3R-ACPD significantly facilitated both, with the delay of CFK acquisition.Injection of acquisition and consolidation of information in a passive avoidance 6-ODA in EK rats is acconpanied by acquisition situation. AP7, the competitive NMDA receptor antagonist, and MK-801 enhancement of CFk. 'Thus,CA-crgic system of the non-competitive NMDA receptor antagonist totally abolished the brain involves difierant .:Jays in rcguldtion of cognitive Jrocesses in r~ts,oridinallydiffe- positive effect of 1S,3R-ACPD on acquisition of information, while only rlng by the level of these syst5ens activity AP7 abolished the facilitatory effect of 1S,3R-ACPD on consolidation (tile incrensad rloradre rialine level in dI.:ii rsts processes. The locomotor and exploratory activity of experimental artd increases doua~iineand serotonin levels groups injected with IS,3R-ACPD, AP7, MK-801 and AP7 or MK-801 in AR-onos) and by emotional ?!eactivity to before 1S,3R-ACPD did not differ from the activity of control rats. The cxtre~!~alstinluli. results of the present study indicate that NMDA receptor plays an important role during the activation of the metabotropic glutamate receptors by I S,3R-ACPD.

MOTION DETECTION LEARNING OF RANDOM SACCADIC EYE MOVEMENTS ENHANCE THE STIMULUS SPECIFIC ADAPTATION IN INFEROTEMPORAL CORTEX OF DOT PATTERN IN VISUALLY DEPRIVED CATS THE MACAQUE Anna No~icka',~and James L. Ringo2 'Nencki Institute of Experimental Biology, Department of Kalina Burnat. Department of Neurophysiologj. Nencki Institute of Neurophysiology 'University of Rochester, Department of Experimental Biology. 3 Pasteur St.. 02-093 Warsan. Poland. Email: Neurobiology and Anatomy We examined whether saccadic eye movements (SEMs) influence a memory effect (repetition decrement or stimulus specific adaptation - SSA), seen in many cells in inferotemporal cortex It was found previously that detection learnlng of a movlng (IT). The effect consists in a more vigorous response to a novel than to a subsequent re-presentation of an image. At the beginning s~mplelight spot was surprisingly d~fficultnot only for of a trial a fixation mark was foveated by the monkey for 400 ms, binocularly deprlved cats (BD cats) but also for control cats the mark was extinguished, and 200-600 ms later a dot (visual cue) reared wlth open eyes (C cats) In thls study presumably appeared for 14 ms. The visual cue was presented either at a stronger, random dot st~muluswas used Two BD cats and 2 position 10 deg displaced from the fixation mark, which required C cats were used The cats were tralned In a two-choice that the monkey made a SEM to the cued position, or at the dlscr~mlnatlonapparatus for food reward The st~mullwere a original fixation mark, in which case no saccade was required. The movlng vs a statlonary random dot pattern In stage 1 of image was then displayed at the cued position for 400 ms. Each tralnlng, the slze of a stationary stlmulus was 30% of a image was presented twice with the variable number of intervening movlng stlmulus and then was enlarged m steps till loo%, the images. The main result came from the stimulus-selective units recorded from IT. These cells showed a significantly greater SSA veloclty of the movlng st~muluswas 7'1s The BD cats with images presented to the fovea via a saccade than with images reached easily crlterlon for dlscr~mlnatlonperformance w~tha presented, foveally, to the fixating monkey. This was true for 20% or 30% size d~fferencebetween movrng and stationary conditions in which the re-presentation was made without st~mull,the C cats comm~tted20 tlmes more errors w~tha intervening images (paired t-test, t=3.5, P < 0.001), and conditions 40% or 30% size difference In stage 2, both stimuli were of in which the re-presentation was made with one intervening image equal slze and the veloc~tywas 20°/s The BD cats d~dnot (paired t-test, t=3.3, P<0.01). reach criterion w~thin50 sessions, whereas the C cats reached crlterlon easlly Thus, lncrease of the st~mulusveloc~ty dld not chang performance of the BD cats, whereas for the C cats ~t was beneficial For BD cats the size of the st~mulusdominated over the motlon parameter Tuesday, Poster session: Learning, memory . . . 69

Environmental enrichment increases NGF levels in The role of primary experimental experience on further hippocampus and visual cortex and improves spatial discrimination learning in rats. learning in elderly rats. Malgorzata Wqsierska, Grajna Walasek and Kazimierz ZieMski

T. Pham, S. Soderstrom', N. Bogdanovic, B.G. Henriksson, B. Department of Neurophysiology, Nencki Institute of Experimental Biology, Winblad and A.H. Mohammed 3 Pasteur St., 02-093 Warsaw, Poland Dept. oJ Clzi~ical Ne'rliroscience nnii Fnrlzily Medicine, Knrolinskn Ii~stitz~tet,5-141 86 Hziiiilinye, and 'Dept. uf Deaeloprilental Ne~irosc~ence,Uppsnln Uniarrsity, 5-751 23 Uppsnla, Szveilen When either forward or backward procedures for classical defensive conditioning have been superimposed on bar pressing for food they evoked Available evidence indicates the aging brain shows opposite effects on instrumental responding. The forward conditioned stimulus elicited suppression of bar presses indicating acquisition of fear. The backward plastic changes in response to environmental influence. stimulus caused enhancement of bar presses indicating acquisition of opposite In previous work we found that adult rats housed for 30 motivation: the safety state. Previously it has been shown that rats did not days in enriched environmental condition (EC) discriminate darkness and noise conditioned stimuli both paired uith shock accordmg to the same contingency. Howver, the enhancement elicited by compared to animals housed in impoverished condition backward stimuli was more prononunced during noise than during darkness (IC) had higher nerve growth factor (NGF) levels in presentation (Walasek et al. 1995*). hippocampus and were better in spatial learning. In the In the present experiment of either fomdor backward CER training on present study rats were housed in EC for a much longer discrimination of darkness and noise stimuli introduced subsequently and presented according to the opposite contingency uas studied. The signalling value period - during adulthood and as they approach old age. of discriminated stimuli uas tested in active avoidance situation. Additionally, Male Sprague-Dawley rats were housed in EC or IC for 14 retention of signalling properties of stimuli uas checked in original CER months, tested for spatial learning and sacrificed for situation. During transfer test in bw-way avoidance situation the tendency for analysis of NGF levels in olfactory bulbs, frontal cortex, better discrimination betwen darkness and noise stimuli uas observed in rats starting with the forward procedure. Performance during retraining session occipital cortex, hippocampus, striatum, hypothalamus showed full retention of signalling values of conditioned stimuli acquired during and cerebellum. EC rats were better in spatial learning discrimination stage. than IC rats, and had higher NGF levels in the ') Walasek G , Weslerska M , Zlellriskl K (1995) Condltionlng of fear and condkioning of safety In hippocampus and visual cortex. These results provide rats Acta Neurobioi EXD55 121-132 further evidence for the critical involvement of NGF in EC-induced neural and behavioural plasticity, and are compatible with the proposition that the brain maintains its capacity for structural reorganization with increasing age.

THE EFFECT OF INFANTILE NONAVERSIVE AND Effect of social housing conditions on reactivity of rats AVERSIVE STIMULATION ON ADULT EMOTIONAL REACTIVIlY IN RATS Grazyna Walasek, Malgorzata Wqsierska, Janusz Blaszczyk and Krzysztof Dqbrowski Tomasz Werka, Janusz Biaszczyk, Katarryna Tajchert, Graiyna Walasek and Malgorzata Wqsierska Department of Neurophysiology, Nencki Institute of Experimental Biology, 3 Pasteur St. 02-093 Warsaw, Poland.

Department of Neurophysiology, Nencki lnstlute of Experimental The effect of social conditions on learning abilities was studied using Biology, 3 Pasteur St., 02-093 Warsaw, Poland. conditioned emotional response (CER) paradigm. In tw groups of rats the forward procedure for classical defensive conditioning uas superimposed on ongoing alimentary instrumental bar presses. Typically, the forward conditioned Two groups (4 ss each) of 3 week old rat pups were exposed stimulus elicited a suppression of bar presses, indicating acquisition of fear. Twnty rats wre used. During the first tw months of life, rats wre to different behavioral treatment in attempt to determine the reared in a standard colony. Then animals wre housed indvidually (Group IN), experimental manipulation influence on aduk behavior. Every day for i.e, one rat in one cage (16cm x 40cm x 25cm). Remained twlve animals two weeks Group NA obtained 15 minute handling whereas Group A (Group SO) wre housed commonly, i.e. six rats in one cage (48cm x 40cm x in the same time was treated with various aversive stimulators. The 25cm) Additionally, only rats from Group SO wre subjected to special applied aversive stimuli were changed every day according to handling procedure in an enriched environment. following list: immobilization in a small box or by fuing rat's tail to the Generally, in Group SO significantly lowr level of bar presses rate uas ground, shaking in an enclosure, swimming in 20" C cold water, seen than in Group IN. Moreover, generalized freezing to contextual and exposure to: 70 dB noise, to 2 kHz tone, to a sharp light, to a dog, and conditioned cues have been observed, resulting in a wak acquisition of classical finally tilting in a cage. The acoustic startle response (ASR) was defensive conditioning. Fast wakening of the suppressive properties of the measured after 5 day break and then repeated afler next four weeks. second part of defensive stimulus has been noticed already from the second day The latency of the ASR was significantly shorter in Group NA in of CER training. On the contrary, in rats from Group IN a clear discrimination between contextual and signalling cues has been observed already on the second comparison to Group A, indicating less tolerance to novelty in rats with day of conditioned training. the infantile nonaversive stimulation. Twenty days afler finishing ASR These results suggest that different housing conditions may caused tests classical defensive response was trained using the CER method. changes in animals emotionality resulting in a strong deficit of learning abilities In contrast to Group A, low base-line level of the alimentary revealed by a wak acquisition of defensive conditioned response. instrumental responding, and markedly generalized fear on contextual and conditional cues were observed in Group NA. These resuks suggested that early nonaversive stimulation clearly enhanced adult emotional responding whereas infantile aversive stimulation decreased rats emotionality 70 Tuesday, Poster session: Learning, memory . . .

THE TWO HEMISPHERES OF THE HUMAN BRAIN DIFFER IN SUBJECTIVE CONTOUR ILLUSION: SEX RELATED VISUAL INFORMATION PROCESSING CARRIED BY MAGNO- LATERALIZATION EFFECT AND PARVOCELLULAR CHANNELS: A PERCEPTUAL TEST A.Grabowska'18, 0. Szymafuka'2J, A. Nowicka"', M. Kwiecien"', K. Iwona Szatkowska and Anna Grabowska Rymar~zyk'~~ Nencki Institute of Experimental Biology, Department of "'Nencki Institute of Experimental Biology Dept. of Neurophysiology, Warsaw, Neurophysiology and '"Central Hospital of the Medical Academy, Warsaw, Poland It is widely expected that right hemisphere processes the incoming The processing of visual information in primates is accomplished hy two information in a global, holistic way whereas the left hemisphere does it in an parallel visual pathways: magno- and parvocellular channel. The analytical or sequential manner. One could expect, therefore. the visual illusions magnocellular channel is more sensitive to low spatial frequencies. This to operate more strongly within the right than within the left hemisphere. as they system is thought to be involved in global analysis of visual scenes. The depend on global, configural properties of perceived patterns. The aim of our parvocellular channel is more sensitive to high spatial frequencies and is study was to investigate the effect of left and right brain damage on subjective involved in identification of visual patterns, especially small, local details. contours illusion. Twenty three patients with right hemisphere damage. 27 It has heen hypothesized that the two hemispheres differ in their ahility patients with left hemisphere damage and 18 control subjects participated in the to process visual information carried hy these two visual channels experiment. They were presented with a series of six subjective contour triangle (Sergent 1983, 1987). The present experiment aimed at testing this configurations.The series was constructed in such a way that the length of hypothesis by using a task in which figures of various sizes and inducing elements (notches) gradually increased. In the first configuration complexity were compared. The stimuli were presented inpairs, one after notches were very short, thus producing no, or just a weak subjective contour another, each for 100 ms, at an interstimulus interval (ISI) of 50 - 500 effect; in the last configuration they were pretty long, thus evoking strong ms. The subject's task was to indicate (hy pressing one of three huttons) illusion. The.subjects were presented once with each version and were asked to describe all figures they could detect. The strength of illusion was determined as whether the second stimulus was the same, smaller or bigger than the a number of configuratians in the series which produced the illusory percept.The first one. The first stimulus in each pair was exposed unilaterally, results indicate that subjective contour illusion diminishes due to brain lesion, but randomly in the left (LVF) or right (RVF) visual field, and the second this effect does not depend on the localization (anteriorlposterior, one was presented at the centre of the visual field. The reaction times frontalltemporallparietal) of lesion. A lateral effect associated with the subjects' analysis shoved significant interaction between stimulated hemifield and gender was observed: in female subjects both left and right hemisphere damage stimulus size, and between stimulated hemifield and stimulus complexity. had the same disturbing effect, whereas in male subjects only the damage to the Small and more complex stimuli were processed faster in RVF right hemisphere diminished the strength of the perceived illusion.The data presentation conditions than in the LVF presentation conditions. Large support the view that the two hemispheres might play a differential role in and less complex stimuli were processed faster in LVF presentation subjective contour illusion. This hemispheric asynlmetry effect however, is conditions than in the RVF presentation conditions. Our data support the limited to male subjects. The finding confimis the notion that males' brain is view that the two hemispheres may differ in their ability to process visual more lateralized than females' brain. information carried by magno- and parvocellular channel.

Masculinity, femininity and transsexuality. Heart rate patterns in rats during Pavlovian aversive conditioning P. Jelefi, J. Zagrodzka, S. Soltysikl) A. Herman-Jeglihka I, Stanislaw Dulko2, Anna Grabowskal Nencki Institute, 3 Pasteur Str., 02-093 Warsaw, Poland ') University of California Los Angeles, h'europsychiatric Institute, Mental ' Department of Neurophysiology, Nencki Institute of ~i~erimnentalBiology, Retardation Research Center, Los Angeles, CA 90024, USA Warsaw, Poland. Department of Sexology and Pathology in Human Relation in Medical Centre The changes in heart rate (HR) are often used as one of experimental of Postgraduate Education, Warsaw, Poland. measures of fear in Pavlovian conditioning paradigms. The exact meaning of this index is not, however, quite clear. The type of reaction (acceleration, deceleration Gender-related traits and their relation to brain function have recently gained or polyphasic pattern) to the conditioned stimulus (CS) in classical conditioning wide interest. In contrast to earlier studies, presently most researchers accept the depends on the species used, the age of subject as well as on experimental view that individuals need not to be either masculine or feminine but can be and arrangements (restrained vs. free-moving animals). Moreover HR patterns differ often are both (androgynous). The present study tested the distribution of sometimes from one subject to another in the same experimental procedure what masculinity or femininity traits in trailssexuals i.e. individuals who have a desire reflects presumably the individual emotionality of the animals. to live and be accepted as members of the opposite sex. This was done to In order to make the meaning of HR changes more clear we performed examine whether transsexuals exhibit gender traits typical for their anatomical Pavlovian aversive conditioning experiments on rats restrained in special apparatus or 'mental' sex. One thousand and thirty seven students (598 females and 439 enabling the animals to run on the treadmill. Tailshock (3 mA, 100 ms) was used males) and 136 transsexuals (11 1 transsexual females and 25 transsexual males) as a unconditioned stimulus (US). The effects of the following factors were tested: participated in this study. Femininity and masculinity traits were measured by modality of the CS (5s light or tone), the presence and modality of conditioned administrating the Polish version of Bem Sex-Role Inventory. The individuals inhibitor (CI tone or light respectively) that overlapped the last 3s of CS, were classified into four groups: androgenous (high femininity and high administration (i.p.) of anxiolytic and anxiogenic drugs (diazepam - DZ and masculinity traits), masculine (high masculinity and low femininity traits). pentylenetetrazol - PTZ). feminine (high femininity and low masculinity traits) and undifferentiated (low It has been found that the mean pattern of HR reaction to the CS femininity and low masculinity traits) according to the median split method. depended on the CS modality. The light-CS produced HR deceleration while tone- CS resulted in acceleration followed by the deceleration. The difference might be The results showed that transsexuals differ reliably from both controls of the associated with the fact that light is a natural aversive stimulus for rats. CI, same anatomical sex and controls of the same 'mental' sex. Male-to-female irrespective of the modality, induced HR acceleration. The mean HR reaction to transsexuals possess extremely high femininity traits (in comparison to both CS as well as to CI was not influenced by DZ (10 mgkg) and by PTZ control females and males), whereas female-to-male transsexuals are more (10 mgkg). The consistent effect of CI could be interpreted as a reduction of androgenous than both control males and females. This data are related to fear. On the other hand the lack of drugs influence leads to some doubts. One specific sex ratio (prevalence of female-to-male over male-to-female transsexuals) explanation is that the effectiveness of drugs in the doses used is too weak to observed in Poland. affect such autonomic response like HR. It might be also supposed that in our model the HR changes do not reflect the anticipatory fear reaction per se. The HR may be associated with attention (the excitatory and inhibitory trials were randomly scheduled in each session) andlor with the coping strategy i.e. response intention (immobility vs. running). Tuesday, Poster session: Learning, memory

CO~II~~~IJ~~~UIIC~IOIIS~fct11Iilrc11lijfer biiJ/er111g /rot11 CONTRAST SENSITIVITY IN DYSLEXIC CHILDREN

piir~ilettt11i~11I1ig1fib 111 f/ic pi~bt D. Bednarek, A. Grabowska. Matgorzata Lipowska Nencki Institute of Experimental Biology, Dept. of Neurophysiology, Inst. of Psycholgy, University of Gdansk Warsaw. l'ur~rlent ~neningitisas III~CC~IOIIof II~I-voust~ssuc IIIC~~ IC~LIC~ wo~king of central nelvuus systen~ 'l'lre~efo~eIII III~II~C'ibes Developmental dyslexia or Specific Reading Disorder is defined as failure to learn to read not attributable to factors such as depreciating of intellectual ti~~~ctlo~ia~rrigllt be 11s ~esult subnormal intelligence, widespread brain damage, impairment of Sixteen cllildren froin 3 to 18 yeais old, wlro Irad bee11 Iio~l)~tdl~bcd oral language skills and severe sociocultural handicap. Despite a because of purulent nleningit~s,welt: put t111oi1g11an CX~IIIIII~IIOIIdt long lasting research in this field the phenomenon of dyslexia remains unexplained. Recent hypothesis (Lovegrove,W. et al. Medical Acaden~yof (jdalisk '1'0 contirln possible lo~lg-lei111cltccts 1986) proposes that dyslexia may result from impairment of the of this illness there was done nledlcal and ~)sycl~ulogicald~agnoaib magnocellular channel in the visual system. As there is substantial Duiing medical researclles no negative results of sull>~~iiglio~~~ evidence that magnocellular pathway responds optimally to low spatial frequency patterns and is relatively highly sensitive to purulent meningitis in the paat wele fount1 But pbycl~~lt~g~cil) contrast, one might expect contrast sensitivity function in dyslexics resea~chesshowed sonie In seven cases tlrs~ewele I;)LIII~b)o~~ptoiiis to differ from that of good readers (especially within the low of organicity, intellectual status ot' six cliild~a~iwab lo\vzi ~IICII frequency range). Contrast sensitivity was measured in 12 dyslexic and 11 control children. Black and white sine-wave horizontal expected for tlieir age '1'0 realiae these exa~ni~iationswcic i~scd gratings of various (0.5; 1.5; 3.8; 8.3 cldeg) frequencies were Short Intelligence Scale (adapted by M (:I~oyi~o~vsh~),1 Ire Iieirde~ - presented on a computer screen, and the method of limits was used

Ciestalt Test, Raven hlatrices 'I est, Benton - Vlaual I

of illness, eventual coinpl~catioirs and tlici~ i~~tluenceat LO~III~I\C dyslexics.

hnctions of patients Lovegrove, W., et al. 1986. Perception and Psychophysics, 40, 440-444.

A neuropsvcholopical test battery for the assessment of lanrmage Test of acalculia: A pilot study. disorders in right brain damaged patients. Lojek E., Strzemecka J., Trojan M., Kamelitow M. tojek E., Skotnicka M. Faculty of Psychology, Warsaw University Faculty of Psychology, Warsaw University An experimental version of the test assessing besic facility There is an increasing awareness of the language and with calculation in brain damaged patients will be presented. The communication disorders that can arise after right hemisphere test is designed to measure the ability to perform routine (RH) damage. The preparations of a neuropsychological tesi arithmetic calculations, the knowledge of numbers and arithmetic battery for the assessment of these impairments will be presented. signs, abilities to solve arithmetic problems in text tasks. The The battery was developed following the example of the fighi results of pilot study involving brain damaged and healthy persons Hemisphere Language Battery by Bryan (1989). The preseni will be presented. The data will be analysed in terms of theoretical experimental battery involves the tests of metaphor, inference. models of acalculia shown in the approach of cognitive humour, and lexical-semantics. The qualitative and quantitative neuropsychology. results of a pilot study in RH damaged and aphasics patients will also be analysed.